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                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                                        
                                  ------------
                                        
                                   FORM 10-K
                                        
                 ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d)
                     OF THE SECURITIES EXCHANGE ACT OF 1934
                                        
                  For the fiscal year ended December 31, 1998
                                        
                         Commission File Number 1-4166
                                        
                                  ------------
                                        
                              FRONTIER CORPORATION
             (Exact name of Registrant as specified in its charter)
                                        
           New York                                       16-0613330
 (State or other jurisdiction of                       (I.R.S. Employer
   incorporation or organization)                     Identification No.)
 
180 South Clinton Avenue, Rochester, New York             14646-0700
  (Address of principal executive offices)                (Zip Code)
 
       Registrant's telephone number, including area code: (716) 777-1000
                                        
          Securities Registered Pursuant to Section 12(b) of the Act:

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Title of Class                       Name of each exchange on which registered
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Common Stock, par value $1.00 per share             New York Stock Exchange
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        Securities Registered Pursuant to Section 12(g) of the Act: None
                                        
Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or such shorter period that the registrant was required
to file such reports), and (2) has been subject to such filing requirements for
the past 90 days.  Yes  X    No 
                       ---      ---

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K.
           ---

The aggregate market value of the voting stock held by non-affiliates of the
registrant as of March 1, 1999 is $6,113,615,520.  The number of shares
outstanding of Frontier Corporation's common stock (Par Value $1.00 per share)
as of the close of March 1, 1999 is 172,277,729 shares.

                      DOCUMENTS INCORPORATED BY REFERENCE
                                        
(1) Portions of the registrant's 1998 Annual Report to Shareholders including
    Management's Discussion of Results of Operations and Analysis of Financial
    Condition, Consolidated Financial Statements and Notes to Consolidated
    Financial Statements, as presented in Exhibit No. 13 of this Form 10-K, are
    incorporated by reference in Parts I, II and IV hereof.

(2) Portions of the Notice of Annual Meeting and Proxy Statement issued by the
    registrant in connection with its Annual Meeting of Shareholders to be held
    April 29, 1999, as presented in Exhibit No. 99 of this Form 10-K, are
    incorporated by reference in Part III hereof.
<PAGE>
 
PART I

ITEM 1.  BUSINESS

General

     Frontier Corporation ("Frontier" or the "Company") provides integrated
telecommunications services including Internet, Internet Protocol ("IP") and
data applications, long distance, local telephone and enhanced services to
business, carrier, web-centric and targeted residential customers nationwide and
in certain international countries.  Although certain of its subsidiaries date
to 1899, the Company was incorporated in 1920 under the laws of New York State
to take over and unify the properties of a predecessor company and certain
properties of the New York Telephone Company which were located in the same
general territory.  Frontier is headquartered in Rochester, New York.  Through
its Integrated Services segment, the Company is one of the nation's largest long
distance companies.  This segment provides domestic and international voice,
data products, video and audio communications, digital distribution services,
Internet service and other communications products to primarily small to mid-
size business customers, carrier customers, web-centric customers and targeted
consumer markets.  The Company's Local Communications Services segment consists
of 34 local telephone companies, which as of December 31, 1998, serve over one
million access lines in thirteen states and is one of the largest local exchange
service providers in the United States.  The Corporate Operations and Other
segment includes expenses traditionally associated with a holding company,
including executive and board of directors' expenses, corporate finance and
treasury, investor relations, corporate planning, legal services and business
development.  The Other category includes Frontier Network Systems ("FNS"). FNS
markets and installs telecommunications systems and equipment.  This segment
previously included the wireless operations of Minnesota Southern Cellular
Telephone Company ("Minnesota RSA No. 10") and the Company's 69.5% interest in
South Alabama Cellular Communications Partnership RSAs No. 4 and No. 6 ("Alabama
RSA No. 4 and No. 6").  The sale of Minnesota RSA No. 10 was finalized April 30,
1998.  The Alabama interest was sold in January 1997.  The Company also owns a
50% interest in Frontier Cellular, a wireless joint venture with Bell Atlantic
in upstate New York and Pennsylvania that is managed by the Company, and is
accounted for using the equity method of accounting.  This method of accounting
results in the Company's proportionate share of earnings being reflected in the
"Other income" section of the Consolidated Statements of Income.

Merger Agreement with Global Crossing

     On March 17, 1999, the Company announced a definitive merger agreement to
be acquired by Global Crossing Ltd. ("Global Crossing"), the owner and operator
of the world's first independent global fiber-optic network.  The transaction is
currently valued at $11.2 billion based on the March 16, 1999 closing price of
Global

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Crossing shares. The combination of the two companies will create a global
Internet Protocol-based fiber-optic network able to provide customers with
integrated worldwide Internet, data, long distance, local telephone and
conferencing services. Based on already announced networks, the combination will
have 71,000 route miles, over 1 million fiber miles, and offer ultra-high
bandwidth to 159 cities in 20 countries. It will offer global voice, web
hosting, private line, ATM and Internet services.

     Under the terms of the transaction, which has been unanimously approved by
the Boards of Directors of both companies, Frontier shareholders will receive
Global Crossing common shares valued at $62 per Frontier share, as long as
Global Crossing shares trade within a range of $34.56 to $56.78 per share (the
"collar") during a price period prior to closing.  Outside the collar, Frontier
shareholders will receive a fixed number of Global Crossing shares, 1.0919
shares at the top end of the collar and 1.7939 at the bottom of the collar.  In
connection with the transaction, Frontier has granted Global Crossing an option
to acquire up to 19.9% of its outstanding shares at $62 per share as well as a
break-up fee if the merger is terminated for certain reasons.

     Based on market prices as of March 16, 1999, the merged company will be
approximately two-thirds owned by current Global Crossing shareholders and one-
third owned by current Frontier shareholders.  The transaction is expected to
qualify as a tax-free reorganization to the Frontier shareholders and is
anticipated to be accounted for as a purchase.  This transaction is subject to
approval by shareholders of both companies, the Federal Communications
Commission, state and other regulatory authorities.  It is expected that the
transaction will be completed in the third quarter of 1999.

Company Strategy

  The Company's strategy is to be the premier provider of integrated
telecommunications solutions in its target markets. The Company will market
itself to customers as a single source provider of  integrated communications
services, which can include long distance, local, cellular, paging, data,
Internet and enhanced services.  Frontier is committed to growth through
expansion of its existing businesses and relationships, the development of
value-added products and services and through strategic acquisitions.  Frontier
anticipates that public policy will continue to evolve in favor of greater
competition and, as a result, the Company has been positioning itself to compete
aggressively in a marketplace with numerous new competitors.
 
  In 1997, the Company's strategy was defined and actions have been taken to
move toward the goal of becoming a market-driven business.  During the fourth
quarter of 1997, the Company began to divest certain nonstrategic assets and
operations.  These actions included the sale of a portion of the Company's
retail

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prepaid calling card business to SmarTalk Teleservices Inc. in December 1997,
the sale of the Minnesota and Alabama facilities-based cellular businesses in
1998 and 1997, respectively, as well as the sale of certain other nonstrategic
assets during 1998. The Company continues to evaluate the strategic value of
other assets and additional sales are expected from time to time.

  Construction of the Company's Optronics network, as originally announced in
1996, was on schedule through the first half of 1998.  However, delays in the
completion of a small number of segments have moved the expected completion date
of the network into the first half of 1999.  Most segments are now complete and
in operation.  The Company made a commitment to extend this network in 1998, and
that extension is expected to be completed in late 1999.   Through swap
agreements with Enron Communications and WTCI, Frontier will add approximately
4,000 additional route miles in the western half of the United States.  These
agreements will also permit the Company to establish additional redundant  SONET
rings, further enhancing the reliability and performance of the network.  In
addition, in July 1998, Frontier entered into an agreement with Williams
Communications, Inc. to construct an extension of the network into the
southeastern United States.  In aggregate, the Company's Optronics network will
have approximately 20,000 route miles.  As of December 31, 1998, approximately
74% of the original 13,000 route mile Optronics network is carrying traffic.
Continuing network integration efforts are expected to further reduce future
network costs as well as provide new revenue opportunities for the Company.

  The combined technology of the Optronics network and the Nortel DMS-500
switches installed at strategic locations along the network will enable the
Company to expand its ability to provide integrated local and long distance
services nationwide.  In 1998, the Company added ATM and IP capabilities to the
Optronics network which will provide greater speed and service for data
products.  In the fourth quarter of 1997, the Company also introduced a
nationwide frame relay product.  This product complements the Company's voice
services business with a portfolio of additional data services products.  This
technology makes Frontier a nationwide facilities-based provider of integrated
local, long distance and data services.
 
 
Legislative and Regulatory Matters

     The competitive evolution of the telecommunications industry has resulted
in a changing regulatory framework.  In general, state regulatory agencies
exercise authority over the prices charged for the provision of local telephone
and intrastate long distance services, the quality of service provided, the
issuance of securities, the construction of facilities and other matters.  Each
of Frontier's local telephone service companies is regulated by the public
utility regulatory agency of the state in which that company provides local
telephone service and by the Federal

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Communications Commission ("FCC"). To a lesser extent, the Company's interstate
long distance business is also subject to FCC and state jurisdiction.

(a)  Telecommunications Act of 1996.  The Telecommunications Act of 1996
("Telecommunications Act") was enacted on February 8, 1996.  This landmark
legislation significantly modified the Communications Act of 1934 and
established a framework for increased competition in the Local and Integrated
Services segments of the Company's business. The Company views this legislation
as favorable to its operations because Frontier has been able to enter new
markets to provide local service as a competitive local exchange carrier
("CLEC"), as well as derive other benefits from the elimination of barriers to
competition.  In addition to its established local telephone and long distance
base, Frontier has been authorized to provide competitive local services in 33
states, plus Washington D.C., as of December 31, 1998 and has commenced
operations in 32 of these states.

     On August 8, 1996, the FCC released a First Report and Order (the "First
Report and Order") in a core rulemaking proceeding to implement the
Telecommunications Act.  The First Report and Order established guidelines to
promote local competition, affecting the Company and all other competitors in
local telecommunications markets.  On July 18, 1997, the U.S. Circuit Court of
Appeals for the Eighth Circuit reversed portions of the First Report and Order
that provided for pricing based primarily on forward looking, rather than
historical costs, and that would have provided the FCC with substantially more
authority over the compliance by local telephone companies with provisions of
the Telecommunications Act.  On January 25, 1999, the United States Supreme
Court revised, in substantial part, the Eighth Circuit's decision.  The Supreme
Court affirmed the FCC's authority to promulgate rules governing the methodology
by which pricing decisions are to be made.   The Court also found that the
Eighth Circuit should not have addressed the issue regarding the FCC's
jurisdiction to enforce compliance with the Act because this issue was not ripe
for review.  Finally, the Court held that the FCC had not followed the statutory
test for determining which network elements incumbent local exchange carriers
were required to unbundle and ordered the matter sent back to the FCC for
further consideration. Action at the FCC is pending.

     The Act also requires the FCC to restructure the manner in which universal
service support payments are established and distributed.  On May 7, 1997, the
Commission substantially adopted the recommendation of a Federal-State Joint
Board released on November 8, 1996 with respect to universal service.  The FCC's
order increased the amount of financial support to be dedicated to universal
service programs.  The Commission has released numerous subsequent orders that
have modified its original decisions.  Further action is anticipated in this
area.

     On May 16, 1997, the Commission adopted an order that substantially
modified the structure by which local exchange carriers are compensated for
access

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to and use of their networks. This order was implemented effective January 1,
1998. In general, this order encouraged the recovery of some costs that had
previously been recovered through usage-based charges to be recovered through
fixed charges. The FCC has postponed implementation of portions of the order and
additional change is considered likely.

     On October 9, 1997, the FCC ordered carriers that receive "dial around"
calls from payphones (certain calls sent without coins, such as 800 or other
calls, with special access codes) to compensate payphone owners at the rate of
28.4 cents per completed call.  The Court of Appeals for the District of
Columbia Circuit found that the FCC had failed to justify this rate and sent the
matter back to the FCC for further consideration.  On February 4, 1999, the FCC
set the "dial around" compensation rate at 24 cents per completed call
retroactive to October 7, 1997.  This decision is subject to reconsideration and
appeal.

     The FCC has yet to determine how to address the payphone compensation
obligation for the period from November 7, 1996 through October 6, 1997.  The
Company is considering whether to pursue challenges to the FCC order with other
carriers in light of the FCC's February 4, 1999 order.  On July 15, 1998, an
administrative complaint was filed by Bell Atlantic Corp. seeking $3.2 million
in compensation for use of its payphones since October 7, 1997.  On August 17,
1998, an administrative complaint was filed by Ameritech Corp. with the FCC
seeking $1.9 million in compensation for the use of its payphones since October
7, 1997.  On September 1, 1998, SBC Communications Inc. filed an administrative
complaint with the FCC seeking $3.3 million in compensation for the use of its
payphones since October 7, 1997.  On November 24, 1998, U S West Communication
Group filed an administrative complaint seeking $2.5 million in compensation for
the use of its payphones since October 7, 1997.  The filing of the complaints
has had no effect upon the position of the Company with respect to payphone
compensation.  The Company cannot predict the ultimate outcome of any of these
FCC proceedings.

(b)  State Proceedings -- General.  A number of states in which the Company has
local or long distance operations are conducting proceedings related to the
ground rules under which carriers may operate in an increasingly competitive
environment.  The issues that the regulatory agencies are examining include
unbundling of local network elements, local interconnection obligations, dialing
parity for intra-LATA (or short-haul) toll traffic, local number portability,
resale of local exchange service and universal service.  The Company cannot, at
this time, predict how these proceedings will ultimately be resolved, nor when
decisions will be forthcoming.  On balance, the actions taken reflect reasonable
steps consistent with the procompetitive objectives of the Telecommunications
Act.

(c)  Open Market Plan.  The Company began its fifth year of operations under the
Open Market Plan in January 1999. The Open Market Plan promotes
telecommunications competition in the Rochester, New York marketplace by

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providing for (1) interconnection of competing local networks including
reciprocal compensation for terminating traffic, (2) equal access to network
databases, (3) access to local telephone numbers, (4) service provider telephone
number portability, and (5) certain wholesale discounts to resellers of local
services. Results since implementation of the Open Market Plan are considered to
have been constructive for the Company as a whole.

     During the seven year period of the Open Market Plan, the Company will not
be regulated by rate-of-return regulation, but instead, will be regulated under
pure price cap regulation.  Over this period, planned rate reductions of $21.0
million (the "Rate Stabilization Plan") will be implemented for Rochester area
consumers, including $16.5 million of which occurred through 1998, and an
additional $1.5 million which commenced in January 1999.  Rates charged for
basic residential and business telephone service may not be increased during the
seven year period of the Plan.  The Company is allowed to raise prices on
certain enhanced products such as Caller ID and call forwarding.

     The New York State Public Service Commission ("NYSPSC") has issued a Notice
Inviting Comments in which it has proposed to make further changes in pricing
under the Open Market Plan.  These pricing changes could reduce some prices to
competitors for network elements and other offerings, but could also reduce the
amount paid by the Company for reciprocal compensation.  The issues being
addressed by the NYSPSC have been under consideration since 1995.  The Company
cannot predict the ultimate impact of any NYSPSC action in this proceeding,
although it is not expected to be material.  The NYSPSC has also issued orders
on other regulatory issues over time, related to service quality, staff
allocations, provisioning and relations with other carriers.

     Management believes there continues to be significant market and business
opportunities, as well as uncertainties, associated with the Company's Open
Market Plan.  There can be no assurance that the changing regulatory environment
will positively impact the Company.

Dividend Policy

     The Open Market Plan prohibits the payment of dividends by the Company's
subsidiary, Frontier Telephone of Rochester, Inc. ("FTR"), to Frontier if (i)
FTR's senior debt is downgraded to "BBB" by Standard & Poor's ("S&P"), or the
equivalent rating by other rating agencies, or is placed on credit watch for
such a downgrade, or (ii) a service quality penalty is imposed under the Open
Market Plan.  Dividend payments to Frontier also require the FTR's directors to
certify that such dividends will not impair FTR's service quality or its ability
to finance its short and long-term capital needs on reasonable terms while
maintaining an S&P debt rating target of "A."

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     In 1996, FTR failed to achieve the service quality levels required by the
Open Market Plan.  FTR requested a waiver, but was denied.  The NYSPSC's ruling
resulted in a restriction on the flow of cash dividends from FTR to Frontier.
On October 22, 1997, the NYSPSC adopted an order requiring FTR to issue refunds
of approximately $0.9 million, or $2.60 per customer.  Reserves sufficient to
cover the refund were established in 1996. These refunds have been issued.

     On October 15, 1998, the NYSPSC approved a proposal by FTR for revision of
its service incentive plan that:
 
  -  required a rebate of $8.00 per customer to resolve all service penalties
     for 1997 and 1998, such rebates have been issued,
  -  established a rebate/client program for missed appointments, and
  -  increased the amounts at risk for the period 1999-2001 should FTR fail to
     meet required service levels.

     In 1998, the Company completed commitments to the NYSPSC to increase
capital expenditures to a minimum of $80.0 million and added employees in
service-affecting areas.

     The temporary restriction of dividend payments to Frontier will remain in
place until the NYSPSC is satisfied that FTR's service levels demonstrate that
FTR has rectified the service deficiency.

Competition

  The telecommunications industry continues to experience significant changes in
the competitive landscape.  Factors such as industry consolidation,
technological advancement, growth in Internet and data applications and changing
regulatory framework have created economies of scale for some companies and
niche opportunities for others.  Frontier is intent on taking advantage of the
various business opportunities which competition provides in the markets where
it operates as well as in new markets.  The Company is addressing competition by
focusing on its core business and the markets it serves, divesting non-strategic
operations, creating advantages through its infrastructure and sales and
customer care philosophies, and by continuing to reduce its cost base to become
more efficient.

(a)  Integrated Services.  Competition in this line of business is generally
based upon pricing, customer service, network efficiencies and reliability,
service quality and enhanced service offerings.  Frontier views the long
distance industry in three tiers.  The industry is dominated on a revenue basis
by the first tier which is made up of the nation's three largest long distance
providers:  AT&T Corp. ("AT&T"), MCI WorldCom, Inc. ("MCI WorldCom") and  Sprint
Communications, Inc. ("Sprint").  AT&T, MCI WorldCom and Sprint generate more
than 85% of the nation's domestic and international long distance revenue.
Frontier is positioned in the second tier.

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The third tier consists of more than 300 companies with annual revenues of less
than $1 billion each, the majority below $50 million each. The Company targets
small to mid-sized business customers and seeks to provide a level of focus and
attention to customer service that compares favorably with what its larger
competitors offer to large commercial customers. Frontier believes that it is
one of a small number of integrated service companies with the ability to offer
high quality integrated data, local and long distance services to small to mid-
size business customers on a nationwide basis. A number of the Company's
competitors are primarily regional in nature, limited by the size of their
transmission systems, dependent on other parties for their billing services, or
offer only basic long distance services.

  The Regional Bell Operating Companies ("RBOC") are continuing to take actions
to meet the Telecommunications Act's "checklist" for entry into the long
distance market within its region.  To date, several applications for entry have
been rejected by the FCC.  Other applications are pending before regulatory
agencies.  An RBOC that is able to meet the checklist is able to enter the long
distance business in its region only in the states where it is authorized.

  The Company recognizes that a benefit of continuing growth is that it will be
able to compete effectively in the changing telecommunications industry and
avail itself of greater economies of scale and scope in its transport and local
access facilities and in its back office operations.

(b)  Local Communications Services.  The Company faces many competitors in the
provision of equipment and facilities used in connection with its local exchange
networks, as this market has become increasingly competitive in recent years.
The market for the provision of local services itself is now competitive in
Rochester, New York as a result of the Open Market Plan, and the
Telecommunications Act is likely to result in significantly greater competition
in other markets.  Competitive Local Exchange Carrier ("CLEC") activity is
believed to be minimal in the Company's telephone properties outside the
Rochester, New York area.
 
  Long distance companies largely access their end user customers through
interconnection with local exchange companies. These long distance companies pay
access fees to the local exchange companies for this service.   The provision of
access services in Rochester by FTR and elsewhere is considered to be
competitive.

Integrated Services

General

  The Company is one of the nation's largest long distance companies.  The
Integrated Services segment provides domestic and international voice, data
products, video and audio communications, digital distribution services,
Internet

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service and other communications products to primarily small to mid-size
business customers, carrier customers and targeted consumer markets. Results for
this segment also include CLEC services. As explained below, CLEC services are
currently available in 32 states, plus Washington D.C., providing the Company
with the ability to offer integrated data, local and long distance services to
approximately 71% of the United States population. In February 1998, the Company
acquired GlobalCenter Inc. (renamed "Frontier GlobalCenter Inc." or
"GlobalCenter"), a leading provider in digital distribution, Internet and data
services headquartered in Sunnyvale, California. The acquisition of GlobalCenter
and subsequent development and integrative work has assisted the Company in
responding to changes in the nature of calling, expanded use of the Internet and
growth of data transmission.

  The Company operates its own switches, develops and implements its own
products, monitors and deploys its transmission facilities and prepares and
designs its own billing and reporting systems.  The Company focuses primarily on
commercial accounts and certain targeted consumer markets.  In this segment,
calling volume consists primarily of calls made during normal business hours,
which command peak-hour pricing.  The Company's residential subscribers tend to
make most of their calls in the evening and on weekends, when business usage is
lowest.

Products and Services

  The Company provides a variety of integrated telecommunications products and
services to commercial and residential subscribers nationwide designed to meet
the customer's total communications needs.  The bulk of the Company's revenue is
derived from outbound and inbound long distance services which are generally
marketed under the Frontier name.  Many of the Company's integrated products,
however, differ from those of competitors due to the level of value-added
services the Company offers and the flexibility of product pricing to maintain
competitiveness.

  The variety of products and services developed and offered are based upon
market driven requirements of the customer including an expectation that
services can be integrated.  They include: digital distribution and data
services, CLEC services, and voice and other value-added services.

  Digital Distribution and Data Services-The Company's Data Services products
target small to mid-sized businesses and web-centric businesses.  Data services
currently include digital private lines, frame relay, dial-up Internet,
dedicated Internet and web-hosting.  The acquisition of GlobalCenter has
accelerated Frontier's ability to provide an expanded line of data services.
During 1998, Frontier expanded its data services product set that can be
segmented into three product lines: Transport, IP and Application Services.
Transport is the means to transfer data from one location to another.  Product
offerings within this service

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category include dedicated private lines, frame relay, and managed services.
Within the IP product line, we provide the customer with the cost efficiencies
of a public Internet network and the security of a private network. Applications
Services are outsourced applications hosted by the service provider and
integrated into both public and private networks which enable the customer to
access the application at all times. Product offerings within this category
include digital distribution, integrated messaging, and web site hosting.
Digital distribution involves a combination of transport services, consulting
services and professional expertise aimed at providing customers with customized
Web based data services.

  CLEC Services-The Company provides competitive local telephone service bundled
with the Company's other integrated services through its CLEC product offering.
The CLEC offering is provided either using the Company's local switching
equipment in locations where it is available or on a resale basis.  As of
December 31, 1998, the Company was providing local services as a CLEC, together
with a complete range of long distance products, in 32 states plus Washington
D.C.  Most of that coverage was provided via resale of services of incumbent
local exchange carriers.  Within that footprint, CLEC service also was provided
initially from Frontier's own switches in New York, Boston and Minneapolis.
Since then, Frontier expanded its coverage to approximately two-thirds of the
United States and turned up facilities-based service in a total of thirteen
metropolitan areas by the end of 1998.  Facilities-based service is being
offered in cities that are on the Company's Optronics network, which will
provide Frontier with the opportunity to expand its offerings of combined local
and long distance services into additional markets, control access costs, and
leverage the Optronics network.  As of the end of 1998, Frontier is serving in
excess of 208,000 CLEC ANIs, or access lines as compared to 100,000 CLEC ANIs at
the end of 1997.  Frontier's objective is to have the capability to offer local
services in 33 states, plus Washington D.C., covering 74% of the population of
the United States by the end of 1999.

  Value-added Services-The Company's value-added services are aimed primarily at
the business subscriber, although the Company also offers products for
residential customers.  Value-added services provide cost-effective solutions
for both simple and complex communications applications and include calling
cards, teleconferencing, broadcast fax, voice mail and cellular and paging
services.

  The calling card is a personal communication tool that can provide access to
teleconferencing, voice mail, information services such as stock quotes and
weather information, Flexible Call Routing of toll free service, Call Delivery
for immediate or future message delivery, Directory Assistance and Travel
Connections to hotel, car and airline reservation systems.  Using a calling
card, customers can call to any domestic and most international locations from
the U.S. or numerous international locations.  In addition, the calling card
product enables customers to dial 100 frequently called numbers using their own
toll free number and a four-digit preprogrammed PIN.

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  Frontier Conferencing provides a way for three or more people at different
locations to participate in a joint discussion.  Several options are available:
800 Meet-Me, Dial-Out or Dial-In via a Frontier calling card.  Broadcast Fax
enables the user to fax a single document to multiple locations at the same time
and is designed for the larger fax user who regularly sends information to an
established list.

  Voice Mail Plus with Fax Mail provides an efficient means of always being
accessible (through the use of outcall or pager notification) and never missing
important calls.  With an individual toll-free number, a customer can save,
delete or forward fax and voice messages to other Voice Mail Plus users or
change greetings all on one call.  Customers can also store a fax or
automatically print it at a designated fax machine.

  The Company offers cellular and paging services to both commercial and
residential customers on a single invoice to complement the customer's
integrated services.  Cellular services are offered in 189 markets through
strategic partnerships with major cellular carriers.  The Company believes this
multi-market coverage offers significant value to customers with multiple
locations and high mobility needs.  Expansion into additional markets and new
digital technologies is being pursued for future development.

  The Company also offers nationwide numeric paging through personal toll free
numbers.  When coupled with the Flexible Call Routing feature, nationwide paging
creates a robust travel application.  Local paging service is also available in
selected local franchise markets.

  The Company's toll free services are offered primarily to business customers
on a single invoice, although several residential products are available.  In
addition to basic 800/888 toll-free applications, the Company offers MultiPoint,
which allows customers to terminate calls in different locations based on the
four-digit Personal Identification Number (PIN) the caller enters; GlobalPoint
international service, which completes calls originating in over 40 countries;
and Flex Connect 800, a fractional service which allows multiple residential
customers to reach different terminating locations utilizing a four-digit
security PIN.  The Company also provides a robust line of routing features such
as Flexible Call Routing, which allows customers to change where calls terminate
based on their need; routing and blocking enhancements determined by the area
code, area code and exchange or full ten-digit telephone number of the caller;
time of day and day of week routing; and percent call allocation.

  Toll free services also include Interactive Voice Response ("IVR") services,
including TargetLine, a call prompter that routes callers either by menu options
or prompting them to enter digits for extension routing; InstaLink, a dealer
locator

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routing callers based upon their area code and exchange or zip code; and
PassPort, a network based host interface IVR solution.

  Pricing-Customers subscribe to various products which determine the price per
minute that they pay on their outbound or inbound long distance calls.  Rates
typically vary by the volume of usage, the distance of the calls, the time of
day that calls are made, the region that originates the call and whether or not
the product is being provided on a promotional basis.

  Reporting Services-The Company offers a variety of billing options and media
aimed primarily at business customers.  When a new commercial account is opened,
the customer is offered the opportunity to custom design the format of its
reports.   The Company also offers customers graphic reports of traffic patterns
on a nationwide basis by state, within state by area of dominant influence
("ADI") and within ADI by zip code.  The Company believes these services are
useful to certain customers for direct response advertising and customer service
applications.  The Company also offers its proprietary personal computer
reporting service, known as uCommand, which allows customers to design their own
reports, prepare separate itemized bills, do mark-up reporting and generate
numerous other customer reports.

  800 Services-These services include area code blocking and routing; time of
day routing; Home Connection 800, a fractional 800 service which allows
residential customers to access 800 service utilizing a four-digit security PIN;
Multi-Point 800 service, which allows customers to use accounting codes on an
800 number or route a single 800 number to numerous locations simultaneously;
Follow-Me 800, which allows customers to change call routing and TargetLine 800,
which routes calls to the closest location a customer identifies and provides
custom prompts based upon a customer specific database.
 
Transmission

  The Company endeavors to have sufficient switching capacity, local access
circuits, and integrated services circuits at and between its network switching
centers to permit subscribers to obtain access to the switching centers and its
integrated services circuits on a basis which exceeds industry standards
regarding clarity, busy signals or delays.

  The network currently utilizes a variety of transmission circuits to complete
long distance calls.  The Company's Optronics network will reduce the number of
transmission facilities leased and provide for a more dependable and cost-
effective transmission system.  Currently, Optronics network facilities have
been completed in Texas, California, Nevada, Utah, Colorado, Kansas, Missouri,
Ohio, Pennsylvania, New York, Illinois, Wisconsin, New Mexico, Arizona, Oregon,
Washington, Nebraska, Iowa, Indiana, Michigan, New Jersey, Maryland, Kentucky,

                                       13
<PAGE>
 
Tennessee, Oklahoma and Massachusetts. Completion of the expanded Optronics
network is expected by year end 1999.

  In addition to the Optronics transmission circuits, the network is comprised
of digital microwave systems located in California, New York and Pennsylvania
for which the Company holds FCC licenses, and facilities that have been leased
on a fixed price basis under primarily short-term contracts. While the Company
still has a number of longer term lease contracts, these contracts have annual
"mark-to-market," "circuit portability," and "commitment buy-out" clauses.
These provisions function to keep the price the Company pays at or near current
market rates.  An important aspect of the Company's operation is planning the
mix of the types of circuits and transmission capacity to be used for each
network switching center so that calls are completed on a basis which is cost
effective for the Company without compromising prompt service and high quality
to subscribers.

  The Company's network switching centers house equipment with varying
capacities to meet the anticipated needs of the service origination region(s)
served by the center.  The equipment used by the Company is, for the most part,
designed to permit expansion of its capacity by the addition of standard
components.  If the maximum capacity of the equipment in any center is reached,
the Company upgrades it with higher capacity switching equipment in an effort to
scale the equipment for growth.  The Company is dependent upon local telephone
companies for installing local access circuits and providing related service
when establishing a network switching center.  International service is provided
through both Company owned direct circuits and through contracts with several
international long distance companies to provide high quality international
service at competitive rates.

  It is anticipated that the Optronics network will continue to lower the
Company's current cost structure and expand the Company's transmission
capabilities.  However, the Company cannot definitively project the change in
its cost structure nor assure that the network will be fully completed as
scheduled.

Major Customer

     In 1996, the Company renegotiated its contract with its then largest
carrier customer as the customer was planning to install its own long distance
switching capacity and diversify its traffic distribution to one or more
additional carriers.  Revenue from this carrier comprised approximately 4% of
Frontier's Integrated Services revenue in 1998 as contrasted with 6% and 21% in
1997 and 1996, respectively.  The loss of this customer's one-plus traffic
contributed to lower operating income in 1997 due to lower overall traffic
levels resulting in a higher level of fixed network costs than required by the
remaining volume of business carried by the Company.

Seasonality

                                       14
<PAGE>
 
  The Company's integrated services revenue is subject to certain limited
seasonal variations.  Because most of the integrated services revenue is
generated by commercial customers, the Company traditionally experiences
decreases in long distance usage and revenue from its commercial customers
during vacation and holiday periods.  The effect of commercial seasonality is
evidenced by lower sequential traffic growth in the fourth quarter for these
customers.

Local Communications Services

  The Company's Local Communications Services segment comprises one of the
largest local exchange service providers in the United States.  This segment
consists of 34 regulated telephone operating  subsidiaries in 13 states, serving
in excess of one million access lines.  The local exchange carriers provide
local, toll, access and resale services, sell, install and maintain customer
premises equipment and provide directory services.

  Over the last decade, the Company has invested heavily to install advanced
digital switching platforms throughout all of its switching network, making the
Company one of a small number in the industry to be served by an entirely
digital network for its local exchange companies.

  Frontier has achieved substantial cost reductions through the elimination of
duplicative services and procedures and the consolidation of administrative
functions.  The Company believes that additional cost reductions may be
obtainable from advanced switching platforms and outside plant delivery systems.
The Company intends to pursue additional gains in productivity by investing in
these technologies where feasible, and through reengineering customer service
processes.

  Of the approximately 1,024,726 access lines in service on December 31, 1998,
721,039 were residential lines and 303,687 were business lines.  Long distance
network service to and from points outside of the telephone companies' operating
territories is provided by interconnection with the facilities of interexchange
carriers.

  Frontier is pursuing several alternatives to provide expanded broadband
capabilities to its customers.  To date, the Company has installed over 31,000
fiber miles of fiber based network facilities (over 930 sheath miles) in the
Rochester, New York area to provide its customers with enhanced capacity and to
position the Company to offer new products.  The Company provides expanded
broadband services to select customers, including video-distance learning
arrangements for educational institutions, and access to SONET based fiber rings
for major business customers.

                                       15
<PAGE>
 
  In connection with its integration strategy, the Company has developed a
program known as "Frontier Long Distance", whereby the Company's local exchange
companies resell Frontier's integrated services.  The Company believes that many
customers prefer the convenience of obtaining their long distance service
through their local telephone company and receiving a single bill.  Frontier
Long Distance is currently offered in the product lines of most of the Company's
local telephone exchange companies.  The results of "Frontier Long Distance" are
included as part of the Integrated Services segment.

Environmental and Other Matters

  Except for site specific issues, environmental issues tend to impact  members
of the telecommunications industry in consistent ways.   The Environmental
Protection Agency ("EPA") and other agencies regulate a number of chemicals and
other substances that may be present in facilities used in the provision of
telecommunications service.  These include preservatives in some wood poles,
asbestos in certain underground duct systems and lead in some cable sheathing.
Some components of the Company's network may include one or more of these
substances.  The Company believes that in their present uses, any such
facilities of the Company pose no significant environmental or health risk
derived from EPA regulated substances.  If EPA regulation of any such substance
is increased, or if any facilities are disturbed or modified in such a way as to
require removal, special handling, storage and disposal may be required for any
such facilities removed from use.  At this time the Company is not subject to
any environmental litigation that requires disclosure, except as set out in Item
3, Legal Proceedings.

Year 2000 Issues

  In furtherance to the 8-K filed 1/26/99 and the Company's Annual Report, the
Company's Year 2000 ("Year 2K") project is intended to address potential
processing errors in computer programs that use two digits (rather than four) to
define the applicable year.  The Company's assessment of Year 2K issues is
essentially complete.  Disclosure is warranted because the issues, if unresolved
by the Company and by the many unaffiliated carriers and other firms with whom
the Company interconnects its networks or does business, could have impacts that
are material.  The Company addresses Year 2K issues in four areas:

  State of Readiness. Frontier has developed plans to assess and remediate key
  ------------------                                                          
internally-developed computer systems so they will be Year 2K compliant in
advance of December 31, 1999 and has implemented those plans to a significant
degree.  The plans encompass all operating properties as well as Frontier's
corporate headquarters.  These include both information technology ("IT") and
non-IT compliance.  The plans cover the review, and either modification or
replacement where necessary, of portions of the Company's computer applications,
telecommunications networks, telecommunications equipment and building facility

                                       16
<PAGE>
 
equipment that directly connect the Company's business with customers, suppliers
and service providers.  Implementation of the plan began in 1996 and the Company
believes that substantially all of its internally-developed IT systems are now
compliant.  Final assessments and remediation are expected to be substantially
complete by midyear 1999, leaving the remainder of 1999 for additional system
testing, carrier interoperability testing and other remediation.  These plans
involve capital expenditures for new software and hardware, as well as costs to
modify existing software.  This could include replacement of individual end user
equipment.  Initially, work with IT systems was given priority over work with
non-IT systems, but the Company is comprehensively reviewing its non-IT Year 2K
readiness as well, including communications with third parties who supply or
maintain non-IT systems or significant non-IT subsystems.

  The Company has given special attention to the Year 2K issues involved in its
network, switches and billing systems, and will continue to dedicate significant
resources to these areas as a priority.  The Company has also increased its
resources in areas in which assessment and remediation has not yet reached a
point where management is satisfied with progress.

  Costs.   To date, the Company has committed approximately $7.5 million to Year
  -----                                                                         
2K issues, and anticipates that it will spend an additional $3.0 to $4.6 million
during 1999.  This includes costs directly related to Year 2K assessment and
remediation and the replacement of non-compliant systems, including acceleration
of replacement of non-compliant systems due to Year 2K issues.  A substantial
portion of the total amount has been used for third party assistance in
assessment and remediation.   Another $5 million may be spent to replace end
user equipment.  The source of these funds is cash generated from operations.
The Year 2K projects have not caused the Company to forego or defer, to any
material degree, other critical IT projects.  To date, the costs of addressing
potential Year 2K problems are not considered material to the Company's
financial condition, results of operations or cash flows and have been
consistent with planned expenditures, and future costs are not expected to be
material in such respects.

  Risks.   The Company is engaged primarily in telecommunications lines of
  -----                                                                   
business, and therefore connects directly and indirectly with thousands of other
carriers, inside and outside the United States.  These connections are made
through switching offices of the Company and the other carriers.  The switching
offices were manufactured by and often maintained by third parties.  While many
other carriers have announced plans to engage independently in Year 2K
assessment and remediation for their networks, there is a risk that some
carriers (particularly smaller carriers and carriers outside the United States)
will not address or resolve Year 2K issues, and that telecommunications will
therefore be affected.  If this were to occur, it is likely that the Company
would be affected only to the same degree as the other carriers in the
telecommunications industry.  A Year 2K failure in the network of smaller
carriers would not be likely to have a significant impact on

                                       17
<PAGE>
 
telecommunications generally, or on the Company. However, addressing these risks
is outside the Company's control. In addition, the Company is unable at this
time to assess the degree to which the manufacturers of switches and similar
equipment have completed their assessment and remediation of such equipment and
its associated software with respect to any other carriers. The majority of the
Company's switches are manufactured and supported by entities with a broad base
of similarly situated customers, and who have a vested interest in assuring that
their products will not be affected by Year 2K events, and if affected, will be
remedied promptly. The Company has initiated an inquiry with its primary vendors
and continues to engage in discussions related to Year 2K compliance with many
of them. Another risk to the Company arises with respect to the timely
completion of Year 2K remediation for the processing that occurs in the
Company's IT and non-IT systems, including billing systems. If the Company or
its vendors are unable to resolve such processing issues in a timely manner, it
could pose independent risks to the Company's business that could be material.
Accordingly, the Company has devoted resources it believes to be adequate to
resolve all significant identified Year 2K issues in a timely manner, and has
undertaken plans to make information available to customers and others related
to its Year 2K activities. Consistent with the practice of other carriers, the
Company generally has declined to provide Year 2K compliance warranties or other
Year 2K-related contractual promises to customers or other persons. In addition,
the Company is engaged in communications with third party equipment and software
vendors and suppliers of services to verify their Year 2K readiness, and plans
to engage in internetwork testing with other carriers during 1999. Since the
Company's own Optronics network, including the recently announced southeast
expansion, is expected to be substantially deployed before December 31, 1999,
the Company anticipates that the impact of other carriers who may experience
business interruptions would be lessened, and such interruptions are not
currently expected to have material adverse impacts on the Company.

  Contingency Plans.   The Company consistently monitors the progress of its
  -----------------                                                         
Year 2K program.  The Company currently anticipates that it will resolve its
Year 2K issues before the end of 1999, with the exception of any issues that
involve other carriers or suppliers and that are outside of its control.  During
1999, the Company will also monitor efforts undertaken through regulatory
agencies and industry groups to assure that Year 2K preparations are completed
in a timely manner.  The Company has begun to evaluate whether there are areas
for which contingency plans are appropriate (but has not identified any such
areas to date).  Any need for contingency planning will be identified well
before year end.  Because of its prior use of multiple billing systems, the
Company has experience in manual billing consolidation for its carrier
customers, and will always have manual processes available to it.  Contingency
plans will be developed for critical systems if conversion or replacement
projects fall behind schedule, or if internetwork testing should identify
significant risk issues, or if broader industry concerns emerge that management
concludes require such action.

                                       18
<PAGE>
 
Employees and Labor Relations

  As of  December 31, 1998, the Company had 8,151 employees, of which 2,708 were
employees of Local Communications Services, 4,254 were employees of Integrated
Services, and 1,189 were employees of other operations.  At the Rochester, New
York Operating Company, 633 clerical and service workers were represented by the
Rochester Telephone Workers Association ("RTWA") and 730 craft and clerical
employees were represented by the Communications Workers of America, Local 1170
("CWA Local"). The union labor contracts are normally negotiated in three year
cycles.

  Under the current three-year contract between the Company and the RTWA,
effective August 10, 1997, bargaining unit employees will receive a 2.0% general
increase on August 15, 1999.  On August 16, 1998 they received a 2.0% general
increase.  On February 18, 1996 and February 16, 1997 they received a 1.0%
general increase.

  On January 31, 1996, the CWA Local contract expired.  The contract
negotiations reached an impasse, and the Company implemented the terms of its
final offer as of April 9, 1996.  Members of the CWA Local ratified a tentative
agreement with the Company on April 29, 1997 which contained provisions that
differed from the Company's final offer implemented at the time of impasse.  The
differences between the Company's final offer and the agreement that was
subsequently reached and ratified by CWA Local membership are not material.  The
new agreement provides several operational improvements and will result in a
more consistent alignment of benefits with the rest of Frontier.  The CWA Local
continued to appeal one issue with the National Labor Relations Board ("NLRB")
related to the declaration of impasse.   In October 1998, the administrative law
judge found in favor of the Company.  Presently, the Union and the government
are appealing to the NLRB.  The Company cannot predict the final outcome of this
matter at the present time.  The CWA Local and the Company reached a new three
year agreement in December 1998 which is not scheduled to expire until January
2002.
 
  The International Brotherhood of Electrical Workers ("IBEW") currently
represents 186 employees at three of the Company's New York communications
subsidiaries.  These subsidiaries are Frontier Communications of New York,
Frontier Communications of Sylvan Lake and Frontier Communications of AuSable
Valley.  The contracts between employees of Frontier Communications of New York
and Frontier Communications of Sylvan Lake and the IBEW expire January 31, 2001.
The current contract between employees of Frontier Communications of AuSable
Valley and the IBEW expires May 10, 2002.

                                       19
<PAGE>
 
     The Company cannot predict the final outcome of these matters at this 
time and there can be no assurance that there will not be a material impact on
the results of operations. There can be no assurance that as contracts with the
Company's other labor unions expire, successful bargaining of new contract terms
will occur.

Risk Factors

     The Company is subject to several risk factors that should be considered by
current shareholders and prospective investors.  This Report on Form 10-K and
the documents incorporated by reference include forward looking statements as
described under the Private Securities Litigation Reform Act of 1995.  Actual
results may differ materially from those identified in forward looking
statements.  Forward looking statements are identified by such words as
"expects", "anticipates", "believes", "intends", "plans" and variations of such
words and similar expressions.

     Changes in Rates of Growth of the Economy and the Overall Industry

     To some extent, the Company's revenue and earnings per share growth are
related to the overall economy and to the telecommunications industry in
general.  Factors that may influence the Company's performance within the
telecommunications industry include product pricing and development, integration
of services, the effects of competition and the expansion of the business.  The
performance of the economy and the telecommunications  industry could cause the
Company's actual results to vary significantly.

     Competition Risk

     Technological innovation and regulatory changes are accelerating the pace
of competition for telecommunications services.  As a result, the Company faces
intensified competition in all aspects of providing telecommunications services.

     There are significant uncertainties surrounding  the introduction of new
products and services and the capital expenditures that will be required by the
Company to remain in a competitive position.  In addition, there are
uncertainties surrounding the impact on competition as a result of the enactment
of the Telecommunications Act.

     Acquisition Integration

     The Company's growth over the last few years has been driven by its long
distance acquisition program and internal growth.  In the last year, the Company
has altered its strategy to place significantly greater emphasis on acquisitions
and growth in the Internet and data area.  This growth strategy involves certain
operational and financial risks.  The operational risks include the possibility
that

                                       20
<PAGE>
 
implementation of an acquisition does not provide the economies of scale or
synergies anticipated by management. Successful integration and expansion of the
Company's network as a result of the acquisitions is dependent on management's
ability to anticipate market growth, install facilities, consolidate databases,
obtain rights of way and negotiate leases economically and efficiently. The
integration of a growing employee base and the elimination of redundant
operations and facilities has required and will continue to require significant
management resources. Although management's plans are to minimize the risks
associated with acquisitions, there can be no assurance that acquired businesses
will be assimilated effectively into the Company.

     Contingent Liabilities

  The Company and a number of its subsidiaries are continuously involved in
various judicial and administrative proceedings involving matters incidental to
the business.  Unless otherwise stated specifically, the Company believes that
the probable outcome of any of these matters, or the combination of all of the
matters, will not have a material adverse effect on the Company's consolidated
results of operations or financial position.  However, there can be no assurance
that the resolution of these matters will not be contrary to management's
expectations.

ITEM 2.  PROPERTIES

  The Company's Integrated Services segment owns property which includes:
Optronics and copper cable, switching equipment, microwave equipment, real
estate and miscellaneous office and work equipment.  The Company's Integrated
Services segment also leases facilities or transmission capacity from other
carriers.

  The Company's Local Communications Services segment owns telephone properties
in their respective operating territories which include:  connecting lines
between customers' premises and the central offices; central office switching
equipment; buildings, land and miscellaneous property and customer premise
equipment.  The central office switching equipment includes digital switches and
peripheral equipment.  The connecting lines include aerial and underground
cable, conduit, poles, wires and microwave equipment.  These facilities are
located on public streets and highways or on privately owned land.  The Company
has permission to use these lands pursuant to local governmental consent or
lease, permit, franchise, easement or other agreement.

  The Company owns or leases the land and buildings in which its central
offices, warehouse space, office and traffic headquarters are located.  Frontier
Corporation's headquarters are located in a leased seven story building at 180
South Clinton Avenue, Rochester, New York.  The lease expires in 2014.

ITEM 3.  LEGAL PROCEEDINGS

                                       21
<PAGE>
 
     On June 11, 1992, a group of corporate plaintiffs consisting of Cooper
Industries, Inc.; Keystone Consolidated Industries, Inc.; The Monarch Machine
Tool Company; Niagara Mohawk Corporation and Overhead Door Corporation commenced
an action in the United States District Court for the Northern District of New
York seeking contribution from fifteen corporate defendants, including Rotelcom
Inc., a wholly-owned subsidiary of the registrant held through intervening
subsidiaries (now named FNS).  The plaintiffs seek environmental response costs
incurred by the plaintiffs pursuant to a consent decree entered into by
plaintiffs with the United States EPA.  Two additional defendants were named in
1994.  In addition to FNS, the current defendants are: Agway, Inc.; BMC
Industries, Inc.; Borg-Warner Corporation; Elf Atochem North America, Inc.; Mack
Trucks, Inc.; Motor Transportation Services, Inc.; Pall Trinity Micro
Corporation; The Raymond Corporation;  Redding-Hunter, Inc.; Smith Corona
Corporation; Sola Basic Industries, Inc.; Wilson Sporting Goods Company; Phillip
A. Rosen; Harvey M. Rosen; City of Cortland and New York State Electric & Gas
Corporation.

     The consent decree concerned the clean-up of an environmental Superfund
site located in Cortland, New York.  It is alleged that the corporate defendants
disposed of hazardous substances at the site and are therefore liable under the
Comprehensive Environmental Response, Compensation and Liability Act.  On
November 21, 1997, the EPA issued a Proposed Remedial Action Plan" ("PRAP").  In
the PRAP, the EPA outlined four alternative plans for remediating the site.
Recently, a number of parties, excluding the Company, have reached agreements
with the EPA to fund certain future remedy costs at the site consistent with the
PRAP.  There has been no allocation of liability by the Court as among or
between the plaintiffs or defendants.

     Since February 1994, a significant number of former American Sharecom, Inc.
("ASI") shareholders have filed and amended several and various complaints in
Hennepin County (Minnesota) District Court.  Included among the defendants are
ASI, its former principal shareholders, Steven Simon and James Weinert, and
Frontier.  These suits allege generally that Simon and Weinert, with and through
ASI, embarked upon a scheme to gain control of ASI and acquire all of its stock
through common law fraud, breach of fiduciary duty and certain violations of the
Minnesota Business Corporation Act.  This Act requires shareholders in a closely
held corporation to act fairly toward one another and refrain from
misappropriation.  Another action by a few former ASI shareholders who dissented
from the cashout merger that finally took ASI private was recently dismissed by
the federal court in Minnesota.  The claims against Frontier maintain only that
Frontier controls the disposition of the restricted Frontier stock which was
issued to Simon and Weinert in connection with the acquisition of ASI and that
such stock should be held in trust for the benefit of the plaintiffs.  At this
time Simon and Weinert have either negotiated settlements with the majority of
former ASI shareholders who had asserted claims or have succeeded in obtaining
dismissal of many of the lawsuits.

                                       22
<PAGE>
 
     Although it is too early to determine the outcome of the remaining
lawsuits, Frontier, ASI and the other defendants each are contesting the claims.
In connection with the acquisition of ASI by Frontier, Simon and Weinert agreed
to indemnify and defend the Company for these claims.

     On April 10, 1997, Jeff Thompson filed a purported class action on behalf
of himself and all other similarly-situated persons in Circuit Court for Marengo
County Alabama.  Named as defendants are Frontier Corporation, Frontier
Subsidiary Telco, Inc. and Frontier Communications of the South, Inc.
("defendants").  The complaint also reserves the right to add additional
defendants and identifies all of Frontier's telephone subsidiaries.  Concomitant
with filing the complaint, plaintiff also filed an ex parte motion for
conditional class certification which the Court granted.  It conditionally
certified a class consisting of "All persons or entities in the United States
who have been charged by defendants or their subsidiaries or affiliates a fee
for `inside wire maintenance' without having given their affirmative acceptance
to a repair service contract; specifically excluded from this class, however,
are all employees, agents, officers, directors and affiliates of any of the
Defendants and all persons or entities who have pending and/or previously filed
individual (non-class) lawsuits against any of the defendants for the same
claims set forth in the Complaint." On January 30, 1998, the Supreme Court of
Alabama issued a writ of mandamus to the trial court ordering it to vacate its
conditional class certification.  In light of the decision of the Alabama
Supreme Court, plaintiffs have agreed voluntarily to dismiss this action with
prejudice.  A stipulation of dismissal with prejudice was entered by the trial
court on February 19, 1999.

     The Open Market Plan discussion in the Business section, Part I, Item 1 of
this document is incorporated herein by reference.

ITEM 4.  SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

     None

                                    PART II
                                        
ITEM 5.   MARKET FOR THE REGISTRANT'S COMMON EQUITY AND RELATED STOCKHOLDER
          MATTERS

     The Company's Common Stock is traded on the New York Stock Exchange (Symbol
- FRO).  The specific information required by this item is as follows:

<TABLE>
<CAPTION>
 
                                           1998              1997            1996
                                          -------          -------          ------
                            Quarter    High     Low     High     Low     High     Low
                            -------   ------  -------  ------  -------  ------  -------
<S>                         <C>       <C>      <C>     <C>     <C>       <C>    <C> 
Highest and lowest
market prices for the         1st     $ 33.44  $24.44  $ 23.25  $17.75  $ 33.25  $28.25
</TABLE> 

                                       23
<PAGE>
 
<TABLE> 
<S>                         <C>       <C>      <C>     <C>     <C>       <C>    <C> 
stock by quarter:             2nd     $33.00   $28.31  $20.50   $15.38  $33.38   $27.75
                              3rd     $36.75   $24.13  $24.19   $19.00  $31.25   $25.88
                              4th     $34.13   $24.81  $25.00   $20.00  $31.88   $19.88

Common stock                  1st          $.2225          $.2175          $.2125
dividends declared            2nd          $.2225          $.2175          $.2125
per share:                    3rd          $.2225          $.2175          $.2125
                              4th          $.2225          $.2225          $.2175
                                           ------          ------          ------

Total Dividends per Year                   $.8900          $.8750          $.8550
 
Number of Shareholders  (at December 31)
 
     Individuals                           29,074          28,432          29,697
     Brokers, nominees and institutions       555             522             509
                                              ---             ---             ---
     Total Shareholders                    29,629          28,954          30,206
</TABLE> 


     On March 1, 1999, the closing price for the Company's stock was $35.69 
per share as published in the Wall Street Journal.

     On January 25, 1999, the Company's Board of Directors approved a change in
its dividend policy which will result in a reduction of the annual common stock
dividend from $0.89 to $0.20 per share annually.  This change in dividend policy
will be effective with the payment of the common stock cash dividend currently
expected to be declared in March, 1999 and paid on May 1, 1999 to shareholders
of record as of April 15, 1999.  The reduction has no effect on the common stock
dividend payable February 1, 1999 to shareholders of record on January 15, 1999,
nor on any outstanding issues of the Company's preferred stock.  This dividend
policy change was approved in order to place the Company more in line with
growth-oriented integrated telecommunication services companies and to allow the
Company to invest more heavily in its growth businesses and provide for greater
strategic alternatives.

ITEM 6.  SELECTED FINANCIAL DATA

     The unaudited information required by this item should be read in
conjunction with the consolidated financial statements and related notes
included in Item 14 contained herein. Historical earnings per share have been
restated to conform with the provisions of Financial Accounting Standards Board
Statement No. 128, and is as follows (in thousands, except per share data):

<TABLE>
<CAPTION>
 
                                            1998         1997        1996         1995         1994
                                         -----------  ----------  -----------  -----------  -----------
<S>                                      <C>          <C>         <C>          <C>          <C> 
Revenues...............................   $2,593,558  $2,374,809   $2,588,519   $2,150,328   $1,667,545
Income from Continuing Operations
 (before Extraordinary Items and
 Cumulative Effect of Changes in
 Accounting Principles)................     $177,543      $31,801    $198,205     $145,129     $187,254
Consolidated Net Income................     $175,788      $31,801    $190,187     $ 22,444     $180,057
 
Basic Earnings per Common Share:
Income before Extraordinary Items and
</TABLE> 

                                       24
<PAGE>
 
<TABLE> 
<S>                                      <C>          <C>         <C>          <C>          <C> 
 Cumulative effect of Changes in
 Accounting Principles.................       $1.03         $.18       $1.19         $.94        $1.25
Extraordinary items....................         ---          ---         ---         (.79)         ---
Cumulative Effect of Changes
 in Accounting Principles..............        (.01)         ---        (.05)        (.01)        (.04)
Basic Earnings per Common Share               $1.02         $.18       $1.14         $.14        $1.21
 
Diluted Earnings per Common Share:
Income before Extraordinary Items and
 Cumulative effect of Changes in
 Accounting Principles.................       $1.02         $.18       $1.18         $.88        $1.15     
Extraordinary items....................         ---          ---         ---         (.74)         ---
Cumulative Effect of Changes
 in Accounting Principles..............        (.01)         ---        (.05)        (.01)        (.04)
Diluted Earnings per Common Share......       $1.01         $.18       $1.13         $.13        $1.11
 
Cash Dividends Declared per
 Common Share..........................      $0.890       $0.875      $0.855       $0.835       $0.815
 
Total Assets...........................  $3,058,743   $2,487,920  $2,229,392   $2,111,415   $2,060,794
 
Long-Term Debt.........................  $1,350,821   $  934,681  $  677,570   $  618,867   $  661,549
</TABLE>

ITEM 7.   MANAGEMENT'S DISCUSSION OF RESULTS OF OPERATIONS AND ANALYSIS OF
          FINANCIAL CONDITION

     The information required by this item is presented in pages 13 through
27 of the Company's 1998 Annual Report to Shareholders which is Exhibit 13 to
this Form 10-K, and is incorporated by reference into this Item 7.


ITEM 7A.  QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

     As of December 31, 1998, the Company does not have any significant
concentration of business transacted with a particular customer, supplier or
lender that could, if suddenly eliminated, severely impact its operations.
However, a portion of the Company's revenues is derived from services provided
to others in the telecommunications industry, mainly resellers of long distance
telecommunications service. Accordingly, the Company periodically performs
ongoing credit evaluations of its larger customers' financial condition to limit
credit risk to the extent possible.

     The Company is also exposed to market risk from changes in interest rates
on long-term debt obligations that impact the fair value of these obligations.
The Company's policy is to manage interest rates through the use of a
combination of fixed and variable rate debt, and to periodically use interest
rate swaps to manage its risk profile.

ITEM 8.   FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

     The consolidated financial statements, together with the report thereon of
PricewaterhouseCoopers LLP, dated January 25, 1999, is presented on pages 28

                                       25
<PAGE>
 
through 49 of the Company's 1998 Annual Report to Shareholders, which is Exhibit
13 to this Form 10-K and is incorporated by reference into this Item 8.

ITEM 9.   CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
          FINANCIAL DISCLOSURE

     None

                                    PART III
                                        
ITEM 10.  DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT

Directors

  The information required by this item for the Directors of Frontier
Corporation is presented on pages 2 through 4 of the definitive proxy statement
provided to shareholders on or about March 12, 1999 in connection with the
Annual Meeting of Shareholders to be held April 29, 1999, which is Exhibit 99 to
this Form 10-K and is incorporated by reference into this Item 10.  Exhibit 99
consists of the Notice of Annual Meeting and the Company's Proxy Statement for
the April 29, 1999 Annual Meeting of Shareholders.



Executive Officers

  Certain information is set forth below regarding the Executive Officers of the
Company as of March 22, 1999.  Each officer serves for a period of one year or
until a successor is elected.

<TABLE>
<CAPTION>
                                                      Other Positions Held
                           Position and                  During the Past
      Name (Age)           Offices Held                     Five Years
----------------------------------------------------------------------------------
<S>                       <C>               <C> 
Robert L. Barrett (57)    Executive Vice    From March 1996 to December 1998
                          President and     he was also President-Network Systems
                          President -       & Services.  From May 1995 to March
                          Technology since  1996 he was President and Executive
                          December 1998     Vice President and Chief Technology
                                            Officer of Banc One Corporation1.
                                            From May 1991 to May 1995 he was
                                            President and Chief Operating Officer
                                            of Banc One Services Corporation./1/
 
David R. Carey (45)       Senior Vice       From December 1995 to March
                          President -       1997 he was Chief Executive


</TABLE> 

                                       26
<PAGE>
 
<TABLE> 
<S>                       <C>               <C> 
                          Marketing         Officer and President of LG&E
                          since             Natural Inc.  From January 1994
                          October 1997      to December 1995 he was Senior
                                            Vice President - Operations of
                                            Louisville Gas & Electric Co./2/
 
Jeremiah T. Carr (55)     Executive Vice    From May 1995 to January 1997 he
                          President         was Senior Vice President.
                          and President -   From January 1995 to May 1995
                          Frontier          he was President and Chief Executive
                          Operations since  Officer of Frontier Telephone of Rochester,
                          January 1997      Inc. and President-Telephone Group.
                                            From November 1993 to December
                                            1994 he was Corporate Vice President
                                            and President - Telephone Group.
 
Joseph P. Clayton (49)    Chief Executive   From August 1997 to March 1999 he was
                          Officer since     Chief Executive Officer and President.
                          March 1999        From June 1997 to August 1997 he
                                            was President and Chief Operating
                                            Officer.  From March 1992 to December
                                            1996 he was Executive Vice President-
                                            Marketing & Sales--Americas & Asia
                                            of Thomson Multimedia./3/


Donald F. Detampel (43)   Senior Vice       From February 1996 to December
                          President and     1998 he was President-Frontier
                          President-        ConferTech.  From April 1990 to
                          Frontier          February 1996 he was President -
                          GlobalCenter      Schneider Communications.
                          since December
                          1998
 
James G. Dole (40)        Senior Vice       From October 1997 to December
                          President since   1998 he was also Controller.
                          October 1997      From August 1997 to October 1997 he
                                            was Vice President and Controller.
                                            From January 1995 to August 1997 he
                                            was Vice President - Business
                                            Development.  From November 1993
                                            to January 1995 he was Corporate
                                            Strategic Planning Director.
 
Joseph Enis (54)          Treasurer since   From June 1994 to December 1994

</TABLE> 

                                       27
<PAGE>
 
<TABLE> 

<S>                       <C>               <C> 
                          January 1995      he was Director of Finance.  From
                                            1992 to June 1994 he was Treasurer of
                                            National Service Industries./4/
 
Rolla P. Huff (42)        President and     From June 1998 to March 1999 he
                          Chief Operating   was Executive Vice President
                          Officer since     and Chief Financial Officer.
                          March 1999        From August 1983 to June 1998 he
                                            held various management positions
                                            with AT&T, including  President of
                                            Central US AT&T Wireless./5/

Martin T. McCue (48)      Senior Vice       Since July 1997 he serves as
                          President and     General Counsel to the Company.
                          General Counsel   From July 1997 to January 1998 he
                          since January     was Vice President and General
                          1998              Counsel.  From January 1995 to
                                            July 1997 he was Corporate Vice
                                            President - Legal, Planning and
                                            Regulatory.  From April 1994 to
                                            January 1995 he was Corporate Vice
                                            President - Planning & Legal.  From
                                            December 1993 to April 1994 he was
                                            Corporate Vice President - Planning.



Donna L. Reeves-          Senior Vice       From September 1996 to October
Collins (38)              President and     1997 she was President - Western
                          President - Sales Region Long Distance Sales.  From
                          since October     December 1994 to September 1996
                          1997              she was President and Chief Operating
                                            Officer of Upstate Cellular Network (a
                                            joint venture).  From September 1993
                                            to December 1994 she was Vice
                                            President-Consumer Service Long Distance.


Josephine S. Trubek (56)  Corporate         From January 1990 to April 1993 she
                          Secretary since   was General Counsel and Secretary.
                          April 1993
</TABLE> 

                                       28
<PAGE>
 
/1/  Banc One is one of the largest bank holding companies in the U.S.  Banc One
     Services Corporation is a subsidiary of Banc One.

/2/  Louisville Gas & Electric Co. is a public utility corporation.

/3/  Thomson Multimedia is one of the largest manufacturers of consumer
     electronics in the world.

/4/  National Service Industries is a public company with businesses in
     lighting, textile rentals and specialty chemicals.

/5/  AT&T Corp. is the largest telecommunications provider in the U.S.  AT&T
     Wireless is a subsidiary of AT&T.

Section 16(a) Beneficial Ownership Reporting Compliance

  The information required by this item for the compliance with section 16(a) of
the Exchange Act is presented on page 7 of the definitive proxy statement
provided to shareholders on or about March 12, 1999 in connection with the
Annual Meeting of Shareholders to be held April 29, 1999, which is Exhibit 99 to
this Form 10-K and is incorporated by reference into this Item 10.  Exhibit 99
consists of the Notice of Annual Meeting and the Company's Proxy Statement for
the April 29, 1999 Annual Meeting of Shareholders.
 
ITEM 11.  EXECUTIVE COMPENSATION

     The information required by this item is presented on page 6 of the
Company's Proxy Statement (which was provided to shareholders on or about March
12, 1999 in connection with the Annual Meeting of Shareholders to be held on
April 29, 1999) under the caption "Compensation of Directors" and on pages 8
through 18 under the captions "Report of Committee on Management," "Performance
Graph," "Compensation of Company Management," and "Compensation Committee
Interlocks and Insider Participation in Compensation Decisions," and is
incorporated by reference into this Item 11.  The Company's Proxy Statement is
found at Exhibit 99 to this Form 10-K.  Exhibit 99 consists of the Notice of
Annual Meeting and the Company's Proxy Statement for the April 29, 1999 Annual
Meeting of Shareholders.

ITEM 12.  SECURITY OWNERSHIP OF CERTAIN BENEFICIAL
          OWNERS AND MANAGEMENT

     The information required by this item is presented in the "Management and
Directors Stock Ownership Table as of February 12, 1999" and the "Stock
Ownership of Certain Beneficial Owners Table as of December 31, 1998" under the
caption "Stock Ownership of Management, Directors and Certain Beneficial Owners"
on pages 6 through 7 of the definitive Proxy Statement for the Annual

                                       29
<PAGE>
 
Meeting of Shareholders to be held April 29, 1999, and is incorporated by
reference into this Item 12.

ITEM 13.  CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

     The information required by this item is presented under the sub-caption
"Employment Contracts" on page 17 of the Definitive Proxy Statement for the
Annual Meeting of Shareholders to be held April 29, 1999 and is incorporated by
reference into this Item 13.

                                    PART IV

ITEM 14.  EXHIBITS, FINANCIAL STATEMENT SCHEDULE AND REPORTS ON FORM 8-K


(a)  1.   Index to Financial Statements
                                                               Page*
                                                               ----
          Report of Management                                  28
          Report of Audit Committee                             28
          Report of Independent Accountants                     28
          Business Segment Information                          29
          Consolidated Statements of Income                     30
          Consolidated Balance Sheets                           31
          Consolidated Statements of Cash Flows                 32
          Consolidated Statements of Shareholders' Equity       33
          Notes to Consolidated Financial Statements         34-49

          *Pages 28 through 49 are incorporated by reference from the
           indicated pages of the 1998 Annual Report to Shareholders.



     2.   Financial Statement Schedule for the years ended December 31,
          1998, 1997 and 1996:
 
          Report of Independent Accountants on Financial Statement Schedule

          Schedule II - Valuation and Qualifying Accounts and Reserves


          All other schedules are omitted because they are not applicable
          or the required information is shown in the financial statements
          or notes thereto.

     3.   See Exhibit Index for list of exhibits filed with this report.

                                       30
<PAGE>
 
          The Registrant hereby agrees to furnish the Commission a copy of each
          of the Indentures or other instruments defining the rights of security
          holders of the long-term debt securities of the Registrant and any of
          its subsidiaries for which consolidated or unconsolidated financial
          statements are required to be filed.
 
(b)  Reports on Form 8-K.

     No reports on Form 8-K were filed during the quarter ended December 31,
  1998.

     The following reports on Form 8-K were filed subsequent to the quarter
     ended December 31, 1998 through March 19, 1999.

 
     SEC Filing Date        Item No.       Financial Statements
     ---------------        --------       --------------------
         1/26/99                5                    Yes
         1/26/99                5                    Yes
         3/19/99              5,7                    No

(c)  Refer to Item 14(a)(3) above for Exhibits required by Item 601 of
     Regulation S-K.

(d)  Schedules other than set forth in response to Item 14(a)(2) above for which
     provision is made in the applicable accounting regulations of the
     Securities and Exchange Commission are not required under the related
     instructions or are inapplicable, and therefore have been omitted.

                                       31
<PAGE>
 
                       REPORT OF INDEPENDENT ACCOUNTANTS
                                        
                        ON FINANCIAL STATEMENT SCHEDULE



To the Board of Directors and
Shareholders of
Frontier Corporation


Our audits of the consolidated financial statements referred to in our report
dated January 25, 1999 appearing on page 28 of the 1998 Annual Report to
Shareholders of Frontier Corporation (which report and consolidated financial
statements are incorporated by reference in this Annual Report on Form 10-K)
also included an audit of the Financial Statement Schedule listed in Item
14(a)(2) of this Form 10-K. In our opinion, based on our audits, this Financial
Statement Schedule presents fairly, in all material respects, the information
set forth therein when read in conjunction with the related consolidated
financial statements.


/s/PricewaterhouseCoopers LLP
-----------------------------
PRICEWATERHOUSECOOPERS LLP
January 25, 1999
Rochester, New York



                                        

                                       32
<PAGE>
 
FRONTIER CORPORATION
     SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS AND RESERVES FOR THE YEAR
     ENDED DECEMBER 31, 1998
     (Table 1 of 3)



In thousands of dollars

<TABLE> 
<CAPTION> 
                                                               Additions
                                                    --------------------------------
                                       Balance at     Charged to      Charged to
                                       beginning       costs and         other                        Balance at
            Description                  of year       expenses        accounts       Deductions      end of year
            -----------                ---------      ----------      ----------      ----------     ------------
<S>                                    <C>            <C>             <C>             <C>            <C> 
Reserve for uncollectible accounts
                                         $25,100         $74,587         $10,159 (1)     $71,890 (2)    $37,956
                                         =======         =======         =======         =======        =======

Deferred tax asset valuation
allowance                                $22,906              $0              $0          $3,467        $19,439
                                         =======              ==              ==          ======        =======


Acquisition related reserves              $4,198              $0              $0          $4,198             $0
                                          ======              ==              ==          ======             ==

Restructuring reserves                   $16,200              $0              $0         $16,200             $0
                                         =======              ==              ==         =======             ==
</TABLE> 



(1) Primarily recoveries of uncollectible accounts.
(2) Uncollectible accounts written off.
(3) Included  primarily in "Property,  plant, and equipment" in the Consolidated
    Balance Sheets.

                                       33
<PAGE>
 
FRONTIER CORPORATION
         SCHEDULE II - VALUATION  AND  QUALIFYING  ACCOUNTS AND RESERVES FOR THE
         YEAR ENDED DECEMBER 31, 1997
         (Table 2 of 3)


In thousands of dollars

<TABLE> 
<CAPTION> 

                                                               Additions
                                                    --------------------------------
                                       Balance at     Charged to      Charged to
                                       beginning       costs and         other                        Balance at
            Description                  of year       expenses        accounts       Deductions      end of year
            -----------                ----------     ----------      ----------      ----------      -----------
<S>                                    <C>             <C>            <C>             <C>             <C> 
Reserve for uncollectible accounts
                                         $31,519         $54,216          $9,030(1)      $69,665(2)     $25,100
                                         =======         =======          ======         =======        =======

Deferred tax asset valuation
allowance                                $21,066          $5,528              $0         $ 3,688        $22,906
                                         =======          ======              ==         =======        =======


Acquisition related reserves             $40,796              $0              $0         $36,598        $ 4,198(3)
                                         =======              ==              ==         =======        =======    


Restructuring reserves                        $0         $43,000              $0         $26,800        $16,200(4)
                                              ==         =======              ==         =======        =======    
</TABLE> 


(1) Primarily recoveries of uncollectible accounts.
(2) Uncollectible accounts written off.
(3) Included  primarily in "Property,  plant, and equipment" in the Consolidated
    Balance  Sheets.
(4) Included primarily in "Other liabilities" in the Consolidated Balance
    Sheets.

                                       34
<PAGE>
 
FRONTIER CORPORATION
         SCHEDULE II - VALUATION  AND  QUALIFYING  ACCOUNTS AND RESERVES FOR THE
         YEAR ENDED DECEMBER 31, 1996
         (Table 3 of 3)

In thousands of dollars

<TABLE> 
<CAPTION> 
                                                               Additions
                                                    --------------------------------
                                       Balance at     Charged to      Charged to
                                       beginning       costs and         other                        Balance at
            Description                  of year       expenses        accounts       Deductions      end of year
            -----------                ----------     ----------      ----------      -----------     -----------
<S>                                    <C>             <C>            <C>             <C>             <C> 
Reserve for uncollectible accounts       $28,515         $76,184         $10,102(1)      $83,282(2)      $31,519
                                         =======         =======         =======         =======         =======

Deferred tax asset valuation
allowance                                $23,887          $1,605              $0         $ 4,426         $21,066
                                         =======          ======              ==         =======         =======


Acquisition related reserves             $83,149              $0              $0         $42,353         $40,796(3)
                                         =======              ==              ==         =======         =======    

</TABLE> 
(1) Primarily recoveries of uncollectible accounts.
(2) Uncollectible accounts written off.
(3) Included  primarily in "Property,  plant and equipment" in the Consolidated
    Balance Sheets.

                                       35
<PAGE>
 
                                  SIGNATURES

     Pursuant  to the  requirements  of  Section  13 or 15(d) of the  Securities
Exchange Act of 1934, the registrant has duly caused this report to be signed on
its behalf by the undersigned, thereunto duly authorized.

                                                 FRONTIER CORPORATION
                                                      (Registrant)



                                                By:   /s/Joseph P. Clayton
                                                    ----------------------------
                                                         Joseph P. Clayton
                                                         Chief Executive Officer
                                                         Date: March 22, 1999


     Pursuant to the  requirements  of the  Securities  Exchange Act of
1934,  this report has been signed below by the  following  persons on behalf of
the registrant and in the capacities and on the dates indicated.


By: /s/Joseph P. Clayton                 By:   /s/Rolla P. Huff        
    ------------------------------           ---------------------------------
       Joseph P. Clayton                          Rolla P. Huff
       Chief Executive Officer                    President and
       and Director                               Chief Operating Officer
       Date:  March 22, 1999                      (principal accounting officer)
                                                  Date:  March 22, 1999

                *                                                
------------------------------------           ---------------------------------
Patricia C. Barron                               Raul E. Cesan
Date:  March 22, 1999                            Date:  March 22, 1999

                *                                               *
------------------------------------           ---------------------------------
Brenda E. Edgerton                               Jairo A. Estrada
Date:  March 22, 1999                            Date:  March 22, 1999

                *                                               
------------------------------------           --------------------------------
Michael E. Faherty                               Alan C. Hasselwander
Date:  March 22, 1999                            Date:  March 22, 1999

                                                                *
------------------------------------           ---------------------------------
Eric Hippeau                                     Robert J. Holland, Jr.
Date:  March 22, 1999                            Date:  March 22, 1999

                *                                               
------------------------------------           ---------------------------------
Douglas H. McCorkindale                          James F. McDonald
Date:  March 22, 1999                            Date:  March 22, 1999

                *                                               
------------------------------------ 
Leo J. Thomas
Date:  March 22, 1999

*By:   /s/ Rolla P. Huff                       Manually signed powers of 
     -------------------------------           attorney for each Director are 
          Rolla P. Huff                  attached hereto and filed
          Attorney-in-Fact                     herewith pursuant to Regulation 
                                               S-K Item 601(b)24 as Exhibit 24.

                                       36
<PAGE>
 
                             FRONTIER CORPORATION
                                 EXHIBIT INDEX

Exhibit
Number          Exhibit Description                  Reference
------          -------------------                  ----------
  3.1           Restated Certificate of              Incorporated by reference
                Incorporation dated                  to Exhibit 3.1 to Form 10-K
                January 24, 1995                     for the year ended
                                                     December 31, 1995
                                              
  3.2           Amendment to Restated                Incorporated by reference
                Certificate of Incorporation         to Exhibit 3.2 to Form 10-K
                dated April 9, 1995                  for the year ended
                                                     December 31, 1995
                                              
  3.3           By-Laws                              Filed herewith
                                              
  4.1           Indenture between the Company        Incorporated by reference
                and Manufacturers Hanover            to Exhibit 4.12 to Form
                Trust Company, Trustee,              10-K for the year ended
                dated September 1, 1986              December 31, 1986
                                              
  4.2           First Supplemental Indenture         Incorporated by reference
                made by the Company to               to Exhibit 4(b) to
                Manufacturers Hanover Trust          Registration Statement
                Company, Trustee, dated              33-32035
                December 1, 1989              
                                              
  4.3           10.46% Non Negotiable                Incorporated by reference
                Convertible Debenture due            to Exhibit 4.14 to Form
                October 27, 2008 from the            10-K for the year ended
                Company to The Walters Trust         December 31, 1988
                                              
  4.4           9% Debenture due                     Incorporated by reference
                August 15, 2021                      to Exhibit 4.16 to Form
                                                     10-K for the year ended
                                                     December 31, 1991
                                              
  4.5           Indenture between the                Incorporated by reference
                Company and Chase Manhattan          to Exhibit 4.5 to Form
                Bank, N.A. dated August 9,           10-K for the year ended
                1995                                 December 31, 1995
                                              
  4.6           Indenture, dated May 21, 1997        Incorporated by reference
                between the Company and Chase        to Exhibit 4.1 to Form 8-K
                Manhattan Bank, NA as Trustee        filed May 23, 1997

                                       37
<PAGE>
 
4.7      Supplemental Indenture between                Incorporated by reference
         the Company and Chase Manhattan Bank,         to Exhibit 4.7 to Form
         NA as Trustee                                 10-K for the year ended
                                                       December 31, 1997
                                                       
4.8      $200 Million Credit Agreement                 Filed herewith
         dated November 10, 1998 with                  
         Chase Manhattan Bank, Fleet Bank,             
         Marine Midland Bank                           
                                                       
4.9      $275 Million Credit Agreement                 Filed herewith
         dated November 10, 1998 with                  
         Chase Manhattan Bank, Fleet Bank,             
         Marine Midland Bank                           
                                                       
10.1     Joint Venture Agreement dated                 Incorporated by reference
         March 9, 1993 by and between                  to Exhibit 10.13 to Form
         Rochester Tel Cellular Holding                10-K for the year ended
         Corporation and New York Cellular             December 31, 1992
         Geographic Service Area, Inc.                 
         together with Exhibit A                       
         thereto                                       
                                                       
10.2     Plan for the Deferral of                      Incorporated by reference
         Directors Fees                                to Exhibit 10.34 to Form
                                                       10-K for the year ended
                                                       December 31, 1994
                                                       
10.3     Directors' Common Stock Deferred              Incorporated by reference
         Growth Plan                                   to Exhibit 10.36 to Form
                                                       10-K for the year ended
                                                       December 31, 1994
                                                       
10.4     Management Stock Incentive                    Incorporated by reference
         Plan dated April 26, 1995                     to Exhibit 10.23 to Form
                                                       10-K for the year ended
                                                       December 31, 1995
                                                       
                                                       
10.5     Executive contract with supporting            Incorporated by reference
         offer letter for Mr. Barrett                  to Exhibit 10.25 to Form
                                                       10-Q for the quarter
                                                       ended March 31, 1996 

                                       38
<PAGE>
 
10.6     Restated Directors                            Incorporated by reference
         Stock Incentive Plan                          to Exhibit 10.27 to Form
         dated April 24, 1996                          10-Q for the quarter
                                                       ended March 31, 1996 
                                                       
10.7     Employee Stock Option Plan                    Incorporated by reference
                                                       to Exhibit 10.28 to Form
                                                       10-Q for the quarter
                                                       ended March 31, 1996
                                                       
10.8     IRU Agreement between Qwest                   Incorporated by 
         Frontier Communications International         reference 
         Communications Corp. and                      to Exhibit 10.11 to Form
         Inc. dated October 18, 1996.                  10-K for the year ended
         (CONFIDENTIAL TREATMENT                       December 31, 1996
         GRANTED FOR CERTAIN PORTIONS                  
         OF THIS EXHIBIT)                              
                                                       
10.9     Restated Supplemental                         Incorporated by reference
         Management Pension Plan                       to Exhibit 10.12 to Form
                                                       10-K for the year ended
                                                       December 31, 1996
                                                       
10.10    Restated Supplemental                         Incorporated by reference
         Retirement Savings Plan                       to Exhibit 10.13 to Form
                                                       10-K for the year ended
                                                       December 31, 1996
                                                       
10.11    Form of management contracts                  Incorporated by reference
         as amended with each of Messrs.               to Exhibit 10.7 to Form
         Massaro and Carr                              10-K for the year ended
                                                       December 31, 1996
                                                       
10.12    Form of management contracts with             Incorporated by reference
         Ms. Reeves-Collins and Mr. Carey              to Exhibit 10.21 to Form
                                                       10-Q for the quarter
                                                       ended September 30, 1997
                                                       
10.13    Amendment No. 1 to the Management             Incorporated by reference
         Stock Incentive Plan                          to Exhibit 10.22 to Form
                                                       10-Q for the quarter
                                                       ended September 30, 1997
                                                       

                                       39
<PAGE>
 
10.14    Amendment No. 1 to Supplemental               Incorporated by reference
         Management Pension Plan                       to Exhibit 10.21 to Form
                                                       10-K for the year ended
                                                       December 31, 1997
                                                       
10.15    Executive  contract with Mr. Clayton,         Incorporated by reference
         effective January 1, 1998                     to Exhibit 10.15 to Form
                                                       10-K for the year ended
                                                       December 31, 1997
                                                       
10.16    Service Continuation Agreement with           Incorporated by reference
         collateral documentation with Mr. Massaro,    to Exhibit 10.24 to Form
         effective December 29, 1997                   10-K for the year ended
                                                       December 31, 1997
                                                       
10.17    Management contract with Mr. McCue,           Incorporated by reference
         effective January 1, 1998                     to Exhibit 10.25 to Form
                                                       10-K for the year ended
                                                       December 31, 1997
                                                       
10.18    Executive contract with Mr. Huff,             Incorporated by reference
         effective May 22, 1998                        to Exhibit 10.1 to
                                                       Registration Statement
                                                       333-72333 filed
                                                       February 12, 1999
                                                       
10.19    1998 Executive Compensation Program           Filed herewith
                                                       
10.20    Amendment No. 1 to Employees'                 Filed herewith
         Stock Option Plan                             
                                                       
10.21    Amendment No. 2 to Management                 Filed herewith
         Stock Incentive Plan                          
                                                       
10.22    Amendment No. 3 to the Management             Filed herewith
         Stock Incentive Plan                          
                                                       
10.23    Amendment No. 2 to Supplemental               Filed herewith
         Management Pension Plan                       
                                                       
10.24    Executive contract with Mr. Detampel          Filed herewith
                                                       
10.25    Pension Bridging Agreement with               Filed herewith

                                       40
<PAGE>
 
         Mr. McCue                                     
                                                       
11       Computation of Diluted Earnings               Filed herewith
         Per Share                                     
                                                       
                                                       
                                                       
13       Specified portions (pages 13                  Filed herewith
         through 49 of the Company's                   
         Annual Report to Shareholders                 
         for the year ended December 31, 1998          
                                                       
21       Subsidiaries of Frontier Corporation          Filed herewith
                                                       
23       Consent of Independent                        Filed herewith
         Accountants - PricewaterhouseCoopers LLP      
                                                       
24       Power of Attorney for a                       Filed herewith
         majority of Directors naming                  
         Josephine S. Trubek attorney-in-fact          
                                                       
27       Financial Data Schedule                       Filed herewith
                                                       
99       Proxy Statement for the                       Filed herewith
         Annual Meeting of Shareholders

                                       41