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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM 10-K


[X]      ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
         EXCHANGE ACT OF 1934 [NO FEE REQUIRED]

For the fiscal year ended December 31, 1998


[ ]      TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
         SECURITIES EXCHANGE ACT OF 1934 [NO FEE REQUIRED]

For the transition period from ________ to ________.

Commission File Number:  0-16947

                     PEOPLES HERITAGE FINANCIAL GROUP, INC. 
             ------------------------------------------------------
             (Exact name of registrant as specified in its charter)

                 MAINE                                        01-0437984       
    ---------------------------------                   ----------------------
      (State or other jurisdiction                         (I.R.S. Employer
    of incorporation or organization)                   Identification Number)

            P.O. BOX 9540
         ONE PORTLAND SQUARE
           PORTLAND, MAINE                                    04112-9540
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(Address of principal executive offices)                      (Zip Code)

       Registrant's telephone number, including area code: (207) 761-8500

   Securities registered pursuant to Section 12(b) of the Act: Not Applicable

          Securities registered pursuant to Section 12(g) of the Act:

                          COMMON STOCK, $.01 PAR VALUE
                          ----------------------------
                                 Title of Class

                         PREFERRED STOCK PURCHASE RIGHTS
                         -------------------------------
                                 Title of Class

Indicate by check mark whether the Registrant (1) has filed all reports required
by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the
preceding 12 months 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. [X]

As of March 19, 1999, the aggregate market value of the 103,021,370 shares of
Common Stock of the Registrant issued and outstanding on such date, excluding
the 1,048,674 shares held by all directors and executive officers of the
Registrant as a group (excluding the effects of unexercised stock options), was
$1.9 billion. This figure is based on the last sale price of $18.41 per share of
the Registrant's Common Stock on March 19, 1999, as reported in THE WALL STREET
JOURNAL on March 22, 1999. Although directors of the Registrant and executive
officers of the Registrant and its subsidiaries were assumed to be "affiliates"
of the Registrant for purposes of this calculation, the classification is not to
be interpreted as an admission of such status.

Number of shares of Common Stock outstanding as of March 19, 1999: 104,070,044

                       DOCUMENTS INCORPORATED BY REFERENCE

         List hereunder the following documents if incorporated by reference and
the part of the Form 10-K into which the document is incorporated:

(1)      Portions of the Annual Report to Stockholders for the year ended
         December 31, 1998 are incorporated by reference into Part II, Items 5-8
         and Part IV, Item 14 of this Form 10-K.

(2)      Portions of the definitive Proxy Statement for the Annual Meeting of
         Stockholders to be held on April 27, 1999 are incorporated by reference
         into Part III, Items 10-13 of this Form 10-K.

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PART I.

ITEM 1.  BUSINESS

THE COMPANY

         Peoples Heritage Financial Group, Inc. (the "Company") is a multi-bank
and financial services holding company which is incorporated under the laws of
the State of Maine. The Company conducts business from its executive offices in
Portland, Maine and, as of December 31, 1998, 188 offices located in Maine, New
Hampshire and Massachusetts. At December 31, 1998, the Company had consolidated
assets of $10.1 billion and consolidated shareholders' equity of $762 million.
Based on total assets at December 31, 1998, the Company is the largest
independent bank holding company headquartered in northern New England and the
fifth largest independent bank holding company headquartered in New England.

         The Company offers a broad range of commercial and consumer banking
services and products and trust and investment advisory services through three
wholly-owned banking subsidiaries: Peoples Heritage Bank ("PHB"), Bank of New
Hampshire ("BNH") and Family Bank, FSB ("Family Bank"). PHB is a Maine-chartered
bank which operates offices throughout Maine and, through subsidiaries, engages
in mortgage banking, financial planning, insurance brokerage and equipment
leasing activities. At December 31, 1998, PHB had consolidated assets of $4.2
billion and consolidated shareholder's equity of $333 million. BNH is a New
Hampshire-chartered commercial bank which operates offices throughout New
Hampshire. At December 31, 1998, BNH had consolidated assets of $4.3 billion and
consolidated shareholder's equity of $328 million. Family Bank is a
federally-chartered savings bank which operates offices in Massachusetts and
southern New Hampshire. At December 31, 1998, Family Bank had consolidated
assets of $1.8 billion and consolidated shareholder's equity of $141 million.

         Acquisitions have been, and are expected to continue to be, an
important part of the expansion of the Company's business. As of December 31,
1998, the Company had completed three acquisitions accounted for under the
pooling-of-interests method and seven acquisitions accounted for under the
purchase method since January 1, 1994. In addition, on January 1, 1999, the
Company completed the acquisition of SIS Bancorp. Inc. ("SIS"), a holding
company for SIS Bank, which was concurrently merged into Family Bank, and
Glastonbury Bank & Trust Company, a Connecticut chartered bank which conducts
business from eight offices in central Connecticut. Approximately 16,255,885
shares of common stock of the Company were issued in connection with this
acquisition, which was accounted for as a pooling-of-interests. SIS had total
assets of $2.0 billion and shareholders' equity of $139 million at December 31,
1998.

         Unless the context otherwise requires, references herein to the Company
include its direct and indirect subsidiaries.


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BUSINESS OF THE COMPANY

         The principal business of the Company consists of attracting deposits
from the general public through its offices and using such deposits to originate
loans secured by first mortgage liens on existing single-family (one-to-four
units) residential real estate and existing multi-family (over four units)
residential and commercial real estate, construction loans, commercial business
loans and leases and consumer loans and leases. The Company also provides
various mortgage banking services and, as discussed below, various trust and
investment advisory services, as well as engages in equipment leasing, financial
planning, securities brokerage and insurance brokerage activities. The Company
also invests in investment securities and other permitted investments.

         The Company derives its income principally from interest charged on
loans and leases and, to a lesser extent, from interest and dividends earned on
investments, fees received in connection with the sale and servicing of loans,
deposit services and for other services and gains on the sale of assets. The
Company's principal expenses are interest expense on deposits and borrowings,
operating expenses, provisions for loan and lease losses and income tax expense.
Funds for activities are provided principally by deposits, advances from the
Federal Home Loan Bank ("FHLB") of Boston, securities sold under repurchase
agreements, amortization and prepayments of outstanding loans, maturities and
sales of investments and other sources.

         PHB, BNH and Family Bank provide full trust services to their
customers. Each of the Company's banking subsidiaries focuses on offering
employee benefit trust services in which it will act as trustee, custodian,
administrator and/or investment advisor, among other things, for employee
benefit plans for corporate, self-employed, municipal and not-for-profit
employers throughout the Company's market areas. In addition, the Company's
banking subsidiaries serve as trustee of both living trust and trusts under
wills and as such hold, account for and manage financial assets, real estate and
special assets. Custody, estate settlement and fiduciary tax services, among
others, also are offered the Company's banking subsidiaries. At December 31,
1998, the Company had $3.0 billion of assets held by the trust departments of
its banking subsidiaries, which are not included in the Company's consolidated
balance sheet for financial reporting purposes.

         The Company is registered as a bank holding company under the Bank
Holding Company Act of 1956, as amended ("BHCA"), and as such is subject to
regulation and examination by the Board of Governors of the Federal Reserve
System ("Federal Reserve Board"). The Company also is registered as a Maine
financial institution holding company under Maine law and as such is subject to
regulation and examination by the Superintendent of Banking of the State of
Maine ("Superintendent").

         As a Maine-chartered bank, PHB is subject to regulation and examination
by the Superintendent, as a New Hampshire-chartered commercial bank, BNH is
subject to regulation and examination by the New Hampshire Bank Commissioner and
as a federally-chartered savings bank, Family Bank is subject to regulation and
examination by the Office of Thrift Supervision ("OTS"). Each of PHB, BNH and
Family Bank is a member of the Bank Insurance Fund ("BIF") administered


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by the Federal Deposit Insurance Corporation ("FDIC") and as a result also is
subject to regulation and examination by the FDIC.

SUBSIDIARIES

         At December 31, 1998, the Company's only direct subsidiaries were PHB,
Bank of New Hampshire Corporation, a holding company for BNH, Peoples Heritage
Merger Corp., a holding company for Family Bank, and Peoples Heritage Capital
Trust I (the "Trust"). For additional information on the Trust, see Note 12 to
the Consolidated Financial Statements included in Item 8 hereof.

         Set forth below is a brief description of certain indirect non-banking
subsidiaries of the Company.

         Investments in Real Estate. The Company's banking subsidiaries hold
certain investments in real estate. Exclusive of other real estate owned and
investments in office properties and facilities, which are discussed under Item
2 hereof, at December 31, 1998 the Company's banking subsidiaries' investments
in real estate consisted entirely of interests in limited partnerships formed
for the purpose of investing in real estate for lower-income families, elderly
housing projects and/or the preservation or restoration of historically or
architecturally significant buildings or structures. At December 31, 1998, the
Company's banking subsidiaries investments in these limited partnerships had a
carrying value of $18.8 million.

         Equipment Leasing Activities. PHB conducts equipment leasing activities
through Peoples Heritage Leasing Corporation, Inc. ("PHLC"). PHLC is
headquartered in Portland, Maine and engages in direct equipment leasing
activities, primarily involving office equipment, in the Portland, Maine
metropolitan area and elsewhere in the States of Maine, New Hampshire and
Massachusetts. At December 31, 1998, PHLC had $34.9 million of leases
outstanding.

         Financial Planning and Securities Brokerage Activities. PHB conducts
financial planning, investment planning and securities brokerage activities
through Heritage Investment Planning Group, Inc. ("HIPG"). PHB also offers
through HIPG investments in mutual funds and annuities throughout the Company's
market areas. HIPG offers its services to individuals and small businesses from
its office located in Portland, Maine and from certain of the Company's other
locations in Maine, Massachusetts and New Hampshire. Sales professionals at HIPG
are registered representatives of Compulife Investor Services, Inc., a
registered broker/dealer, and all securities brokerage activities are conducted
through Compulife Investor Services, Inc. The sales professionals receive
referrals from the Company's branch offices throughout its market areas.

         Insurance Brokerage Activities. PHB conducts insurance brokerage
activities through MPN Holdings, the holding company for Morse, Payson & Noyes,
which the Company acquired in October 1997, the Catalano Insurance Agency, Inc.,
which the Company acquired in September 1998, and A.D. Davis, Incorporated,
which the Company acquired in December 1998. Morse,


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Payson & Noyes is the largest insurance brokerage firm in Maine. Catalano
Insurance Agency, Inc. is headquartered in Methuen, Massachusetts, and A.D.
Davis, Incorporated is headquartered in North Conway, New Hampshire. During
1998, the Company completed the two acquisitions noted above for an aggregate of
454,864 shares of common stock of the Company and the acquisition of another
insurance brokerage agency, which was merged into Morse, Payson & Noyes, for
cash.

         In addition, PHB conducts insurance sales activities through HIPG,
which offers limited life insurance and long-term care insurance products in
Maine as an agent for Compulife, Inc., in conjunction with the sales of
investment and annuities products.

COMPETITION

         The Company encounters strong competition both in the attraction of
deposits and in the making of real estate and other loans. Its most direct
competition for deposits has historically come from savings institutions,
commercial banks and credit unions with offices in the market areas served by
the Company. The Company also encounters competition for deposits from money
market funds, as well as corporate and government securities. The principal
methods used by the Company to attract deposit accounts include the variety of
services offered, the competitive interest rates offered and the convenience of
office locations, automated teller machines and expanded banking hours.

         The Company's competition for real estate and other loans comes
principally from savings institutions, credit unions, commercial banks, mortgage
banking companies, insurance companies and other institutional lenders. The
Company competes for loans through interest rates, branch locations, loan
maturities, loan fees and the quality of service extended to borrowers and
brokers.

         The Company also experiences significant competition in the offering of
trust services through its subsidiary banks, securities services through HIPG
and insurance products through HIPG and the Company's insurance brokerage
subsidiaries. This competition comes from a sundry of entities, including other
financial institutions, securities brokerage firms and insurance companies.

         In recent years, Maine, New Hampshire and Massachusetts laws have
enabled the acquisition of financial institutions in these respective states by
financial institutions and financial institution holding companies based outside
of these states. As a result, the Company has encountered substantial
competition in its market areas, particularly from out-of-state banking
organizations that have entered the Maine, New Hampshire and Massachusetts
banking markets, and the Company expects to continue to encounter such
competition in the future.

EMPLOYEES

         The Company had approximately 3,334 full-time employees as of December
31, 1998. None of these employees is represented by a collective bargaining
agent, and the Company believes that it enjoys good relations with its
personnel.


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REGULATION OF THE COMPANY

         The following references to laws and regulations which are applicable
to the Company and its banking subsidiaries are brief summaries thereof which do
not purport to be complete and are qualified in their entirety by reference to
such laws and regulations.

         BHCA - General. The Company, as a bank holding company, is subject to
regulation and supervision by the Federal Reserve Board. Under the BHCA, a bank
holding company is required to file annually with the Federal Reserve Board a
report of its operations and, with its subsidiaries, is subject to examination
by the Federal Reserve Board.

         BHCA - Activities and Other Limitations. The BHCA generally prohibits a
bank holding company from acquiring direct or indirect ownership or control of
more than 5% of the voting shares of any bank, or increasing such ownership or
control of any bank, without prior approval of the Federal Reserve Board. As a
result of recent amendments to the BHCA, the Federal Reserve Board generally may
approve an application by a bank holding company that is adequately capitalized
and adequately managed to acquire control of, or to acquire all or substantially
all of the assets of, a bank located in a state other than the home state of
such bank holding company, without regard to whether such transaction is
prohibited under the law of any state, provided, however, that the Federal
Reserve Board may not approve any such application that would have the effect of
permitting an out-of-state bank holding company to acquire a bank in a host
state that has not been in existence for any minimum period of time, not to
exceed five years, specified in the statutory law of the host state.

         The BHCA also generally prohibits a bank holding company, with certain
exceptions, from acquiring more than 5% of the voting shares of any company that
is not a bank and from engaging in any business other than banking or managing
or controlling banks. Under the BHCA, the Federal Reserve Board is authorized to
approve the ownership of shares by a bank holding company in any company the
activities of which the Federal Reserve Board has determined to be so closely
related to banking or to managing or controlling banks as to be a proper
incident thereto. In making such determinations, the Federal Reserve Board is
required to weigh the expected benefit to the public, such as greater
convenience, increased competition or gains in efficiency, against the possible
adverse effects, such as undue concentration of resources, decreased or unfair
competition, conflicts of interest or unsound banking practices.

         Capital Requirements. For a description of the capital adequacy
guidelines adopted by the Federal Reserve Board to assess the adequacy of
capital of bank holding companies, see "Management's Discussion and Analysis of
Financial Condition and Results of Operations - Capital" included in Item 7
hereof.

         Affiliated Institutions. Under Federal Reserve Board policy, the
Company is expected to act as a source of financial strength to each subsidiary
bank and to commit resources to support each subsidiary bank in circumstances
when it might not do so absent such policy. The Federal Reserve


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Board takes the position that in implementing this policy it may require bank
holding companies to provide such support when the holding company otherwise
would not consider itself able to do so.

         A bank holding company is a legal entity separate and distinct from its
subsidiary bank or banks. Normally, the major source of a holding company's
revenue is dividends a holding company receives from its subsidiary banks. The
right of a bank holding company to participate as a stockholder in any
distribution of assets of its subsidiary banks upon their liquidation or
reorganization or otherwise is subject to the prior claims of creditors of such
subsidiary banks. The subsidiary banks are subject to claims by creditors for
long-term and short-term debt obligations, including substantial obligations for
federal funds purchased and securities sold under repurchase agreements, as well
as deposit liabilities. Under the Financial Institutions Reform, Recovery and
Enforcement Act of 1989, in the event of a loss suffered by the FDIC in
connection with a banking subsidiary of a bank holding company (whether due to a
default or the provision of FDIC assistance), other banking subsidiaries of the
holding company could be assessed for such loss.

         Federal laws limit the transfer of funds by a subsidiary bank to its
holding company in the form of loans or extensions of credit, investments or
purchases of assets. Transfers of this kind are limited to 10% of a bank's
capital and surplus with respect to each affiliate and to 20% in the aggregate,
and are also subject to certain collateral requirements. These transactions, as
well as other transactions between a subsidiary bank and its holding company,
also must be on terms substantially the same as, or at least as favorable as,
those prevailing at the time for comparable transactions with non-affiliated
companies or, in the absence of comparable transactions, on terms or under
circumstances, including credit standards, that would be offered to, or would
apply to, non-affiliated companies.

         Limitations of Acquisitions of Common Stock. The federal Change in Bank
Control Act prohibits a person or group of persons from acquiring "control" of a
bank holding company unless the Federal Reserve Board has been given 60 days'
prior written notice of such proposed acquisition and within that time period
the Federal Reserve Board has not issued a notice disapproving the proposed
acquisition or extending for up to another 30 days the period during which such
a disapproval may be issued. An acquisition may be made prior to expiration of
the disapproval period if the Federal Reserve Board issues written notice of its
intent not to disapprove the action. Under a rebuttable presumption established
by the Federal Reserve Board, the acquisition of more than 10% of a class of
voting stock of a bank holding company with a class of securities registered
under Section 12 of the Securities Exchange Act of 1934 would, under the
circumstances set forth in the presumption, constitute the acquisition of
control.

         In addition, any "company" would be required to obtain the approval of
the Federal Reserve Board under the BHCA before acquiring 25% (5% in the case of
an acquiror that is a bank holding company) or more of the outstanding Common
Stock of, or such lesser number of shares as constitute control over, the
Company.


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         Maine Law. Under Maine law, the prior approval of the Superintendent is
required in any case in which (i) any person or company proposes to acquire
control of a Maine financial institution or a Maine financial institution
holding company and (ii) a Maine financial institution or Maine financial
institution holding company proposes to acquire more than 5% of the voting
shares of a Maine financial institution or a Maine financial institution holding
company. In addition, the prior approval of the Superintendent is required for
the acquisition of more than 5% of the voting shares of a financial institution,
whose home state is not Maine, by a Maine financial institution or a Maine
financial institution holding company.

         In addition, any person or company which directly or indirectly
acquires more than 5% of the voting shares of a Maine financial institution or a
Maine financial institution holding company is required within five days of the
acquisition to file with the Superintendent a statement containing specified
information, including the background and identity of the person or company, the
source and amount of funds or other consideration for the purchase and any plans
or proposals which the acquiring person may have to liquidate the financial
institution or financial institution holding company, to sell its assets or
merge it with any company or to make any other major change in its business,
corporate structure or management. Any person or company also must file a notice
with the Superintendent when there is a material change in ownership. Under
Maine law, the acquisition of an aggregate of more than another 5% of the voting
shares is a material change.

         A Maine financial institution holding company may not engage in any
activity other than managing or controlling financial institutions or other
activities deemed permissible by the Superintendent. The Superintendent has by
regulation determined that, with the prior approval of the Superintendent, a
financial institution holding company may engage in those activities which are
permissible for bank holding companies under the BHCA and those activities which
are permissible for savings and loan holding companies under the Home Owners'
Loan Act, and additional activities as specified by regulations.

         New Hampshire Law. New Hampshire law generally prohibits a bank holding
company organized under the laws of New Hampshire or doing business in the State
of New Hampshire from directly or indirectly acquiring ownership or control of
any voting stock of any bank or national bank, if upon such acquisition (i) the
bank holding company would have more than twelve bank affiliates in New
Hampshire, or (ii) the dollar volume of the total of time, savings and demand
deposits in New Hampshire of the bank holding company and all its affiliates
would exceed 20% of the dollar volume of the total of time, savings and demand
deposits of all banks, national banks and federal savings and loan associations
in the State of New Hampshire as determined by the New Hampshire Bank
Commissioner. The above-referenced 20% limitation may be waived by the New
Hampshire Bank Commissioner and the New Hampshire Attorney General if both
determine that it is in the best interests of the State of New Hampshire,
provided that under no circumstances shall the total dollar volume of total
deposits exceed 30%.


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REGULATION OF BANKING SUBSIDIARIES

         General. Each of PHB, BNH and Family Bank is subject to extensive
regulation and examination by the Superintendent, the New Hampshire Bank
Commissioner and the OTS, respectively. Each of the Company's banking
subsidiaries also is subject to regulation and examination by the FDIC, which
insures the deposits of each of the Company's banking subsidiaries to the
maximum extent permitted by law, and certain requirements established by the
Federal Reserve Board. The federal and state laws and regulations which are
applicable to banks regulate, among other things, the scope of their business,
their investments, their reserves against deposits, the timing of the
availability of deposited funds and the nature and amount of and collateral for
loans. The laws and regulations governing the Company's banking subsidiaries
generally have been promulgated to protect depositors and not for the purpose of
protecting stockholders.

         Capital Requirements. Each of the Company's banking subsidiaries is
subject to regulatory capital requirements of the FDIC (in the case of PHB and
BNH) and the OTS (in the case of Family Bank) which are substantially comparable
to the regulatory capital requirements of the Federal Reserve Board applicable
to bank holding companies such as the Company. At December 31, 1998, the
regulatory capital of each of the Company's banking subsidiaries substantially
exceeded applicable requirements.

         Prompt Corrective Action. Section 38 of the Federal Deposit Insurance
Act ("FDIA") provides the federal banking regulators with broad power to take
"prompt corrective action" to resolve the problems of undercapitalized
institutions. The extent of the regulators' powers depends on whether the
institution in question is "well capitalized," "adequately capitalized,"
"undercapitalized," "significantly undercapitalized" or "critically
undercapitalized." Under regulations adopted by the federal banking regulators,
an institution shall be deemed to be (i) "well capitalized" if it has total
risk-based capital ratio of 10.0% or more, has a Tier I risk-based capital ratio
of 6.0% or more, has a Tier I leverage capital ratio of 5.0% or more and is not
subject to specified requirements to meet and maintain a specific capital level
for any capital measure; (ii) "adequately capitalized" if it has a total
risk-based capital ratio of 8.0% or more, a Tier I risk-based capital ratio of
4.0% or more and a Tier I leverage capital ratio of 4.0% or more (3.0% under
certain circumstances) and does not meet the definition of "well capitalized,"
(iii) "undercapitalized" if it has a total risk-based capital ratio that is less
than 8.0%, a Tier I risk-based capital ratio that is less than 4.0% or a Tier I
leverage capital ratio that is less than 4.0% (3.0% under certain
circumstances), (iv) "significantly undercapitalized" if it has a total
risk-based capital ratio that is less than 6.0%, a Tier I risk-based capital
ratio that is less than 3.0% or a Tier I leverage capital ratio that is less
than 3.0%, and (v) "critically undercapitalized" if it has a ratio of tangible
equity to total assets that is equal to or less than 2.0%. The regulations also
provide that a federal banking regulator may, after notice and an opportunity
for a hearing, reclassify a "well capitalized" institution as "adequately
capitalized" and may require an "adequately capitalized" institution or an
"undercapitalized" institution to comply with supervisory actions as if it were
in the next lower category if the institution is in an unsafe or unsound
condition or engaging in an unsafe or unsound practice. The


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federal banking regulator may not, however, reclassify a "significantly
undercapitalized" institution as "critically undercapitalized."

         An institution generally must file a written capital restoration plan
which meets specified requirements, as well as a performance guaranty by each
company that controls the institution, with an appropriate federal banking
regulator within 45 days of the date that the institution receives notice or is
deemed to have notice that it is "undercapitalized," "significantly
undercapitalized" or "critically undercapitalized." Immediately upon becoming
undercapitalized, an institution becomes subject to statutory provisions which,
among other things, set forth various mandatory and discretionary restrictions
on the operations of such an institution.

         At December 31, 1998, each of the Company's banking subsidiaries had
capital levels which qualified it as a "well-capitalized" institution under
applicable laws and regulations.

         FDIC Insurance Premiums. Each of the Company's banking subsidiaries is
a member of the BIF administered by the FDIC, although certain deposits of each
of these entities acquired in acquisitions are insured by the Savings
Association Insurance Fund ("SAIF") administered by the FDIC.

         As an FDIC-insured institution, each of the Company's banking
subsidiaries is required to pay deposit insurance premiums to the FDIC.
Effective January 1, 1997, the assessment schedule for both BIF and SAIF ranges
from 0 basis points (subject to a $2,000 annual minimum) to 27 basis points. In
addition, both BIF-insured institutions and SAIF-insured institutions are
assessed amounts in order for a federally-chartered Finance Corporation to make
payments on it bonds.

         Brokered Deposits. The FDIA restricts the use of brokered deposits by
certain depository institutions. Under the FDIA and applicable regulations, (i)
a "well capitalized insured depository institution" may solicit and accept,
renew or roll over any brokered deposit without restriction, (ii) an "adequately
capitalized insured depository institution" may not accept, renew or roll over
any brokered deposit unless it has applied for and been granted a waiver of this
prohibition by the FDIC and (iii) an "undercapitalized insured depository
institution" may not (x) accept, renew or roll over any brokered deposit or (y)
solicit deposits by offering an effective yield that exceeds by more than 75
basis points the prevailing effective yields on insured deposits of comparable
maturity in such institution's normal market area or in the market area in which
such deposits are being solicited. The term "undercapitalized insured depository
institution" is defined to mean any insured depository institution that fails to
meet the minimum regulatory capital requirement prescribed by its appropriate
federal banking agency. The FDIC may, on a case-by-case basis and upon
application by an adequately capitalized insured depository institution, waive
the restriction on brokered deposits upon a finding that the acceptance of
brokered deposits does not constitute an unsafe or unsound practice with respect
to such institution. The Company's banking subsidiaries had $258 million of
brokered deposits outstanding at December 31, 1998.


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         Community Investment and Consumer Protection Laws. In connection with
its lending activities, each of the Company's banking subsidiaries is subject to
a variety of federal laws designed to protect borrowers and promote lending to
various sectors of the economy and population. Included among these are the
federal Home Mortgage Disclosure Act, Real Estate Settlement Procedures Act,
Truth-in-Lending Act, Equal Credit Opportunity Act, Fair Credit Reporting Act
and Community Reinvestment Act ("CRA").

         The CRA requires insured institutions to define the communities that
they serve, identify the credit needs of those communities and adopt and
implement a "Community Reinvestment Act Statement" pursuant to which they offer
credit products and take other actions that respond to the credit needs of the
community. The responsible federal banking regulator (in the case of the Bank
and FNB, the FDIC and the OCC, respectively) must conduct regular CRA
examinations of insured financial institutions and assign to them a CRA rating
of "outstanding," "satisfactory," "needs improvement" or "unsatisfactory." In
1998, the CRA rating of the Company's banking subsidiaries was either
"outstanding" or "satisfactory."

         Limitations on Dividends. The Company is a legal entity separate and
distinct from its banking and other subsidiaries. The Company's principal source
of revenue consists of dividends from its banking subsidiaries. The payment of
dividends by the Company's banking subsidiaries is subject to various regulatory
requirements.

         Miscellaneous. The Company's banking subsidiaries are subject to
certain restrictions on loans to the Company or its non-bank subsidiaries, on
investments in the stock or securities thereof, on the taking of such stock or
securities as collateral for loans to any borrower, and on the issuance of a
guarantee or letter of credit on behalf of the Company or its non-bank
subsidiaries. The Company's banking subsidiaries also are subject to certain
restrictions on most types of transactions with the Company or its non-bank
subsidiaries, requiring that the terms of such transactions be substantially
equivalent to terms of similar transactions with non-affiliated firms.

         Regulatory Enforcement Authority. The enforcement powers available to
federal banking regulators is substantial and includes, among other things, the
ability to assess civil money penalties, to issue cease-and-desist or removal
orders and to initiate injunctive actions against banking organizations and
institution-affiliated parties, as defined. In general, these enforcement
actions may be initiated for violations of laws and regulations and unsafe or
unsound practices. Other actions or inactions may provide the basis for
enforcement action, including misleading or untimely reports filed with
regulatory authorities.

TAXATION

         Federal Taxation. The Company and its banking subsidiaries are subject
to those rules of federal income taxation generally applicable to corporations
under the Code. The Company and its banking subsidiaries, as members of an
affiliated group of corporations within the meaning of Section 1504 of the Code,
file a consolidated federal income tax return, which has the effect of


                                       10
<PAGE>   12

eliminating or deferring the tax consequences of inter-company distributions,
including dividends, in the computation of consolidated taxable income.

         State Taxation. As a financial institution holding company, the Company
is subject to a separate state franchise tax in lieu of state corporate income
tax. The amount of the tax is the sum of 1% of Maine net income and $.08 per
$1,000 of Maine assets as defined in Maine law. Maine assets are the Company's
total end of the year assets as reported to the United States Government on the
federal income tax return. Maine net income is the Company's net income or loss
as reported by the Company on its consolidated financial statements which is
apportioned to Maine under Maine law.

         The Company is subject to New Hampshire business profits tax based on
federal taxable income attributable to New Hampshire apportionments. The tax is
essentially computed by excluding from taxable income any interest on U.S.
Government obligations, adding back New Hampshire business profits taxes used in
computing federal taxable income, and then multiplying the resulting New
Hampshire taxable income by 7.0%. The computed tax is offset by a credit for any
New Hampshire enterprise tax assessed on the affiliates' compensation, interest
and dividends paid.

         The Company is subject to Massachusetts financial institution excise
tax based on federal taxable income primarily attributable to its Massachusetts
affiliates. The tax is computed by adding back tax-exempt income excluded from
federal taxable income, state income tax/excise taxes deducted from federal
taxable income, and then multiplying the resulting Massachusetts taxable income
by 10.91%. Certain affiliates chartered in Massachusetts pay taxes at less than
statutory rates.

ITEM 2. PROPERTIES

         At December 31, 1998, the Company conducted its business from its
headquarters and main office at One Portland Square, Portland, Maine, and, as of
December 31, 1998, 188 offices located in Maine, New Hampshire and
Massachusetts. For additional information regarding the Company's lease
obligations, see Note 14 to the Consolidated Financial Statements included in
Item 8 hereof.


                                       11
<PAGE>   13

         The following table sets forth certain information with respect to the
offices of the Company as of December 31, 1998.


<TABLE>
<CAPTION>
                                                    Net Book Value of
                                 Number of       Property and Leasehold
   State                      Banking Offices         Improvements          Deposits
-----------                   ---------------    ----------------------    ----------
                                                 (Dollars in Thousands)
<S>                                  <C>                 <C>               <C>       
PHB                                  75                  $27,168           $2,862,122
BNH                                  78                   28,272            2,896,694
Family Bank                          35                   14,515            1,222,429
                                    ---                  -------           ----------
    Total                           188                  $69,955           $6,981,245
                                    ===                  =======           ==========
</TABLE>

ITEM 3.           LEGAL PROCEEDINGS

         The Company is involved in routine legal proceedings occurring in the
ordinary course of business which in the aggregate are believed by management to
be immaterial to the financial condition and results of operations of the
Company.

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

         Not applicable.

PART II.

ITEM 5.           MARKET FOR REGISTRANT'S COMMON STOCK AND RELATED
                  STOCKHOLDER MATTERS

         The information contained under the section captioned "Common Stock
Prices" on page 64 of the Company's Annual Report to Stockholders for the year
ended December 31, 1998 (the "Annual Report") is incorporated herein by
reference.

ITEM 6.           SELECTED FINANCIAL DATA

         The information contained in the table captioned "Selected Five-Year
Consolidated Financial and Other Data" on page 13 of the Company's Annual Report
is incorporated herein by reference.

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

         The information contained in the section captioned "Management's
Discussion and Analysis of Financial Condition and Results of Operations" on
pages 14 through 31 of the Company's Annual Report is incorporated herein by
reference.


                                       12
<PAGE>   14

ITEM 7A.          QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET
                  RISK.

         The information contained in the section captioned "Management's
Discussion and Analysis of Financial Condition and Results of Operations - Asset
and Liability Management" on pages 27 and 28 of the Company's Annual Report is
incorporated herein by reference.

ITEM 8.           FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

         The financial statements and supplementary data required are contained
on pages 32 through 55 of the Company's Annual Report and are incorporated
herein by reference.

PART III.

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

         None.

ITEM 10.          DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT

         Incorporated by reference to "Election of Directors" on pages 2 through
6 and "Executive Officers who are not Directors" on pages 9 and 10 of the
definitive Proxy Statement of the Company, dated March 22, 1999 (the "Proxy
Statement").

ITEM 11.          EXECUTIVE COMPENSATION

         Incorporated by reference to "Compensation of Executive Officers and
Transactions with Management" on pages 7 and 8 and 13 through 16 of the Proxy
Statement.

ITEM 12.          SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND
                  MANAGEMENT

         Incorporated by reference to "Beneficial Ownership of Common Stock by
Certain Beneficial Owners and Management" on pages 11 and 12 of the Proxy
Statement.

ITEM 13.          CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

         Incorporated by reference to "Certain Transactions" on pages 19 and 20
of the Proxy Statement.


                                       13
<PAGE>   15

PART IV.

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

         (a)(1) The following financial statements are incorporated by reference
from Item 8 hereof and the Annual Report to Stockholders included herein as
Exhibit 13:

         Consolidated balance sheets at December 31, 1998 and 1997

         Consolidated statements of income for each of the years in the
         three-year period ended December 31, 1998

         Consolidated statements of changes in shareholders' equity for each of
         the years in the three-year period ended December 31, 1998

         Consolidated statements of cash flows for each of the years in the
         three-year period ended December 31, 1998

         Notes to Consolidated Financial Statements

         Independent Auditors' Report

         (a)(2) All other schedules for which provision is made in the
applicable accounting regulations of the Securities and Exchange Commission are
omitted because of the absence of conditions under which they are required or
because the required information is included in the financial statements and
related notes thereto.

         (a)(3) The following exhibits are included as part of this Form 10-K.


                                       14
<PAGE>   16

<TABLE>
<CAPTION>
EXHIBIT NO.                       EXHIBIT                                               LOCATION
-----------                       -------                                               --------

<S>          <C>                                                                           <C>
3(a)(1)      Amended and Restated Articles of Incorporation of                             (1)
              the Company                                          
3(a)(2)      Amendment to the Articles of Incorporation of the                             (2)
              Company                                              
3(b)         Bylaws of the Company                                
4(a)         Specimen Common Stock certificate                                             (3)
4(b)         Form of Indenture between the Company and Mellon     
              Bank, N.A., as trustee                                                       (4)
4(c)         Form of Debenture due 2000                                                    (4)
4(d)         Amended and Restated Declaration of Trust relating to                         (5)
              Peoples Heritage Capital Trust I, dated as of January
              31, 1997, between the Company and the trustees named 
              therein                                              
4(e)         Form of Common Securities and form of Capital                                 (5)
              Securities of Peoples Heritage Capital Trust I       
              (included as Exhibits to the Amended and Restated    
              Declaration included as Exhibit 4(d))                
4(f)         Indenture, dated as of January 31, 1997, between the                          (5)
              Company and The Bank of New York, as trustee,        
              relating to Junior Subordinated Deferrable Interest  
              Debentures due 2027 of the Company                   
4(g)         Form of Junior Subordinated Deferrable Interest                               (5)
              Debentures due 2027 of the Company (included as      
              Exhibit A to the Indenture included as Exhibit 4(f)) 
4(h)         Series A Capital Securities Guarantee Agreement,                              (6)
              dated as of January 31, 1997, relating to the Series 
              A Capital Securities of Peoples Heritage Capital     
              Trust I                                                                       
4(i)         Common Securities Guarantee Agreement, dated as of                            (6)
              January 31, 1997, relating to the Common Securities  
              of Peoples Heritage Capital Trust I                                           
10(a)        Amended and Restated Severance Agreement between the                          (7)
              Company and William J. Ryan                           
</TABLE>


                                       15
<PAGE>   17

<TABLE>
<CAPTION>
EXHIBIT NO.                       EXHIBIT                                               LOCATION
-----------                       -------                                               --------
<S>          <C>                                                                           <C>

10(b)        Amended and Restated Severance Agreement between the                          (7)
              Company and Peter J. Verrill                         
10(c)        Form of Severance Agreement between the Company and                           (6)
              each of R. Scott Bacon, David D. Hindle, John W.     
              Fridlington, Carol L. Mitchell and Wendy Suehrstedt  
10(d)        Form of Amendment to Severance Agreement between the                          (8)
              Company and each of R. Scott Bacon and David D.      
              Hindle                                               
10(e)        Supplemental Retirement Agreement among the Company,                          (9)
              its subsidiaries and William J. Ryan                 
10(f)        Supplemental Retirement Agreement among the Company,                          (9)
              its subsidiaries and Peter J. Verrill                
10(g)        Supplemental Retirement among the Company, its                                (10)
              subsidiaries and John W. Fridlington                 
10(h)        Form of Supplemental Retirement Agreement among the                           (8)
              Company, its subsidiaries and each of R. Scott Bacon,
              Carol L. Mitchell and Wendy Suehrstedt               
10(i)        Senior Officers' Deferred Compensation Plan, as                               (11)
              amended                                              
10(j)        Directors' Deferred Compensation Plan, as amended                             (11)
10(k)        1986 Stock Option and Stock Appreciation Rights Plan,                       (1)(12)
              as amended                                           
10(l)        1986 Employee Stock Purchase Plan, as amended                               (1)(12)
10(m)        Amended and Restated Restricted Stock Plan for Non-                           (6)
              Employee Directors                                   
10(n)        Amended and Restated 1995 Stock Option Plan for Non-                          (13)
              Employee Directors                                   
10(o)(1)     Amended and Restated Thrift Incentive Plan                                    (6)
10(o)(2)     First Amendment to Amended and Restated Thrift                                (6)
              Incentive Plan                                       
10(p)(1)     Profit Sharing Employee Stock Ownership Plan                                  (14)
10(p)(2)     First Amendment to Profit Sharing Employee Stock                              (7)
              Ownership Plan                                       
</TABLE>


                                       16
<PAGE>   18
<TABLE>
<CAPTION>
EXHIBIT NO.                       EXHIBIT                                               LOCATION
-----------                       -------                                               --------
<S>          <C>                                                                           <C>

10(p)(3)     Second Amendment to Profit Sharing Employee Stock                             (7)
              Ownership Plan                                       
10(q)        1996 Equity Incentive Plan, as amended                                        (15)
10(r)        Bank of New Hampshire Corporation Executive Excess                            (16)
              Benefit Plan for Paul R. Shea                        
10(s)        Supplemental Executive Retirement Plan agreement                              (17)
              between The Family Mutual Savings Bank and David D.  
              Hindle                                               
10(t)        Split Dollar Insurance Agreement between The Family                           (18)
              Mutual Savings Bank and David D. Hindle              
10(u)        Employment Agreement between the Company and F.                               (19)
              William Marshall, Jr.                                
10(v)        Form of Severance Agreement between the Company and                           (20)
              Christopher W. Bramley                               
10(w)        Stockholders Rights Agreement, dated September 12,                            (21)
              1989, between the Company and American Stock Transfer
              & Trust Company, as Rights Agent                     
13           Annual Report to Stockholders for 1998               
21           Subsidiaries of the Company                          
23           Consent of KPMG Peat Marwick LLP                     
27           Financial Data Schedule                              
</TABLE>

----------------------------

(1) Incorporated by reference to the Agreement and Plan of Merger, dated as of
October 27, 1997, between the Company and CFX Corporation, which is included as
Exhibit A to the Prospectus/Proxy Statement included in the Form S-4
Registration Statement (No. 333-23991) filed by the Company with the Securities
and Exchange Commission ("SEC") on December 31, 1997.

(2) Exhibit is incorporated by reference to the proxy statement filed by the
Company with the SEC on March 23, 1998.

(3) Exhibit is incorporated by reference to the Form S-4 Registration Statement
(No. 33-20243) filed by the Company with the SEC on February 22, 1988.


                                       17
<PAGE>   19

(4) Exhibit is incorporated by reference to the Form 8-K report filed by the
Company with the SEC on February 28, 1995.

(5) Exhibit is incorporated by reference to the Form S-4 Registration Statement
(No. 333-23991) filed by the Company with the SEC on March 26, 1997.

(6) Exhibit is incorporated by reference to the Company's Form 10-K report for
the year ended December 31, 1996, filed with the SEC on March 31, 1997.

(7) Exhibit is incorporated by reference to the Company's Form 10-K report for
the year ended December 31, 1995, filed with the SEC on March 29, 1996.

(8) Exhibit is incorporated by reference to the Company's Form 10-K report for
the year ended December 31, 1997, filed with the SEC on March 27, 1998.

(9) Exhibit is incorporated by reference to the Company's Form 10-K report for
the year ended December 31, 1990, filed with the SEC on March 23, 1991.

(10) Exhibit is incorporated by reference to the Company's Form 10-K report for
the year ended December 31, 1994, filed with the SEC on March 30, 1995.

(11) Exhibit is incorporated by reference to the Company's Form 10-K report for
the year ended December 31, 1993, filed with the SEC on March 17, 1994.

(12) An amendment to the 1986 Stock Option and Stock Appreciation Rights Plan is
incorporated by reference to the proxy statement filed by the Company with the
SEC on March 24, 1994, and an amendment to the Employee Stock Purchase Plan is
incorporated by reference to the proxy statement filed by the Company with the
SEC on March 24, 1993.

(13) Exhibit is incorporated by reference to the proxy statement filed by the
Company with the SEC on March 21, 1997.

(14) Exhibit is incorporated by reference to the Form S-1 Registration Statement
(No. 33-53236) filed by the Company with the SEC on November 23, 1992.

(15) Exhibit is incorporated by reference to the Form 10-Q report filed by the
Company with the SEC on November 16, 1998.

(16) Exhibit is incorporated by reference to the Form 10-K report filed by Bank
of New Hampshire Corporation (File No. 0-9517) for the year ended December 31,
1994.

(17) Exhibit is incorporated by reference to the Form 10-K report filed by
Family Bancorp (File No. 0-17252) for the year ended December 31, 1993.


                                       18
<PAGE>   20

(18) Exhibit is incorporated by reference to the Form S-4 Registration Statement
(No. 33-18613) filed by Family Bancorp.

(19) Exhibit is incorporated by reference to the Form 8-K report filed by the
Company with the SEC on January 4, 1999.

(20) Exhibit is incorporated by reference to the Form 8-K report filed by the
Company with the SEC on April 22, 1998.

(21) Exhibit is incorporated by reference to the Form 8-K report filed by the
Company with the SEC on September 13, 1989.

     The Company's management contracts or compensatory plans or arrangements 
consist of Exhibit Nos. 10(a)-(v).

     (b)  Not applicable.

     (c)  See (a)(3) above for all exhibits filed herewith and the Exhibit
Index.

     (d)  There are no other financial statements and financial statement
schedules which were excluded from the Annual Report to Stockholders which are
required to be included herein.


                                       19
<PAGE>   21

                                   SIGNATURES


         Pursuant to the requirements of Section 13 of the Securities Exchange
Act of 1934, the Company has duly caused this report to be signed on its behalf
by the undersigned, thereunto duly authorized.


PEOPLES HERITAGE FINANCIAL GROUP, INC.



By: /s/ William J. Ryan                                    Date: March 22, 1999
    -------------------------------------------
    William J. Ryan
    Chairman, President and Chief
     Executive Officer


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



/s/ Robert P. Bahre                                        Date: March 22, 1999
--------------------------------------------------
Robert P. Bahre
Director


/s/ P. Kevin Condron                                       Date: March 22, 1999
--------------------------------------------------
P. Kevin Condron
Director


/s/ Everett W. Gray                                        Date: March 22, 1999
--------------------------------------------------
Everett W. Gray
Director



/s/ Andrew W. Greene                                       Date: March 22, 1999
--------------------------------------------------
Andrew W. Greene
Director


                                       20
<PAGE>   22

/s/ Katherine M. Greenleaf                                 Date: March 22, 1999
--------------------------------------------------
Katherine M. Greenleaf
Director


/s/ Douglas S. Hatfield                                    Date: March 22, 1999
--------------------------------------------------
Douglas S. Hatfield
Director


/s/ David D. Hindle                                        Date: March 22, 1999 
--------------------------------------------------
David D. Hindle
Director


/s/ Dana S. Levenson                                       Date: March 22, 1999 
--------------------------------------------------
Dana S. Levenson
Director


/s/ Robert A. Marden, Sr.                                  Date: March 22, 1999
--------------------------------------------------
Robert A. Marden, Sr.
Vice Chairman


/s/ Philip A. Mason                                        Date: March 22, 1999
--------------------------------------------------
Philip A. Mason
Director


                                                           Date:  
--------------------------------------------------
John M. Naughton
Director



/s/ Malcolm W. Philbrook, Jr.                              Date: March 22, 1999
--------------------------------------------------
Malcolm W. Philbrook, Jr.
Director


                                       21
<PAGE>   23

/s/ Pamela P. Plumb                                        Date: March 22, 1999
--------------------------------------------------
Pamela P. Plumb
Vice Chairman


                                                           Date:  
--------------------------------------------------
Seth A. Resnicoff
Director


/s/ William J. Ryan                                        Date: March 22, 1999
--------------------------------------------------
William J. Ryan
Chairman, President and Chief
 Executive Officer
(principal executive officer)



/s/ Curtis M. Scribner                                     Date: March 22, 1999
--------------------------------------------------
Curtis M. Scribner
Director



/s/ Paul R. Shea                                           Date: March 22, 1999
--------------------------------------------------
Paul R. Shea
Director


/s/ John E. Veasey                                         Date: March 22, 1999
--------------------------------------------------
John E. Veasey
Director



/s/ Peter J. Verrill                                       Date: March 22, 1999
--------------------------------------------------
Peter J. Verrill
Executive Vice President, Chief Operating Officer,
 Chief Financial Officer and Treasurer (principal financial
 and accounting officer)


                                       22