<PAGE>

                                                                   Exhibit 10.21
                                                                   -------------

                     WARRANT REGISTRATION RIGHTS AGREEMENT

                                 by and between

                               IWO HOLDINGS, INC.

                                      and

              DONALDSON, LUFKIN & JENRETTE SECURITIES CORPORATION

           (an affiliate of Credit Suisse First Boston Corporation),

                             CHASE SECURITIES INC.,

                          BNP PARIBAS SECURITIES CORP.

                                      and

                                UBS WARBURG LLC

                          Dated as of February 2, 2001

                     ______________________________________


               160,000 Warrants Initially Exercisable to Purchase

                   2,000,040  Shares of Class C Common Stock

                     ______________________________________
<PAGE>

                     WARRANT REGISTRATION RIGHTS AGREEMENT

     This Warrant Registration Rights Agreement (this "Agreement") is made and
                                                       ---------
entered into as of February 2, 2001, by and between IWO Holdings, Inc., a
Delaware corporation (the "Issuer"), and Donaldson, Lufkin & Jenrette Securities
                           ------
Corporation (an affiliate of Credit Suisse First Boston Corporation) ("DLJ"),
                                                                       ---
Chase Securities Inc., BNP Paribas Securities Corp. and UBS Warburg LLC
(collectively, including DLJ, the "Initial Purchasers"), which have agreed to
                                   ------------------
purchase 160,000 warrants (the "Warrants") of the Issuer issued pursuant to the
                                --------
Warrant Agreement (the "Warrant Agreement") between the Issuer and Firstar Bank,
                        -----------------
N.A. as warrant agent (the "Warrant Agent").
                            -------------

     The Warrants are being issued and sold in connection with the offering (the
"Offering") by the Issuer of 160,000 Units each consisting of (i) $1,000
 --------
principal amount at maturity of the Issuer's 14% Senior Notes due 2011 (the

"Notes") and (ii) one Warrant. Each Warrant entitles the holder thereof to
------
purchase 12.50025 shares of the Class C common stock, $0.01 par value ("Common
                                                                        ------
Stock"), of the Issuer, subject to adjustment as set forth in the Warrant
-----
Agreement.

     This Agreement is made pursuant to the Purchase Agreement, dated January
26, 2001 (the "Purchase Agreement"), by and among the Issuer, Independent
               ------------------
Wireless One Corporation and the Initial Purchasers.  In order to induce the
Initial Purchasers to purchase the Warrants, the Issuer has agreed to provide
the registration rights set forth in this Agreement.  The execution and delivery
of this Agreement is a condition to the obligations of the Initial Purchasers
set forth in Section 9 of the Purchase Agreement.  Capitalized terms used herein
and not otherwise defined shall have the meaning assigned to them in the Warrant
Agreement.

     The parties hereby agree as follows:

SECTION 1.  DEFINITIONS

     As used in this Agreement, the following capitalized terms shall have the
following meanings:

     Act:  The Securities Act of 1933, as amended.
     ----

     Affiliate:  As defined in Rule 144.
     ----------

     Black Out Notice:  As defined in Section 4(b) hereof.
     -----------------

     Black Out Period:  As defined in Section 3(a) hereof.
     -----------------

     Closing Date:  The date hereof.
     -------------

     Commission:  The Securities and Exchange Commission.
     -----------

     Effectiveness Period:  As defined in Section 3(a) hereof.
     ---------------------

     Exchange Act:  The Securities Exchange Act of 1934, as amended.
     -------------
<PAGE>

     Expiration Date: 5:00 p.m. New York City time on January 15, 2011.
     ----------------

     Holders:  As defined in Section 2 hereof.
     --------

     Prospectus:  The prospectus included in a Registration Statement at the
     -----------
time such Registration Statement is declared effective, as amended or
supplemented by any prospectus supplement and by all other amendments thereto,
including post-effective amendments, and all material incorporated by reference
into such Prospectus.

     Registration Statement:  Any registration statement of the Issuer relating
     -----------------------
to the registration for resale of Transfer Restricted Securities that is filed
pursuant to the provisions of this Agreement and including the Prospectus
included therein, all amendments and supplements thereto (including post-
effective amendments) and all exhibits and material incorporated by reference
therein.

     Rule 144:  Rule 144 promulgated under the Act.
     ---------

     Transfer Restricted Securities:  (a) Each Warrant and Warrant Share held by
     -------------------------------
an Affiliate of the Issuer and (b) each other Warrant and Warrant Share until
the earlier to occur of the date on which (i) such Warrant has been exercised
pursuant to a Registration Statement or (ii) such Warrant Share (other than any
Warrant Share issued upon exercise of a Warrant in accordance with a
Registration Statement) has been disposed of in accordance with a Registration
Statement or distributed to the public pursuant to Rule 144 under the Act.

     Warrant Shares:   Shares of the Issuer's Class C common stock, issuable
     ---------------
upon exercise of Warrants and any "restricted securities" (as defined in Rule
144) issuable upon the conversion or exchange of Class C common stock.

SECTION 2.  HOLDERS

     A Person is deemed to be a holder of Transfer Restricted Securities (each,
a "Holder") whenever such Person is the holder of record of Transfer Restricted
   ------
Securities.

SECTION 3.  SHELF REGISTRATION

     (a) Shelf Registration.  The Issuer shall prepare and cause to be filed
         ------------------
with the Commission on or before 90 days from the Closing Date pursuant to Rule
415 under the Securities Act a Registration Statement on the appropriate form
relating to resales of Transfer Restricted Securities by the Holders thereof and
if permitted by applicable law the exercise of Warrants that are Transfer
Restricted Securities.  The Issuer shall use its reasonable best efforts to
cause the Registration Statement to be declared effective by the Commission on
or before 180 days after the Closing Date.

     To the extent necessary to ensure that the Registration Statement is
available to the Holders entitled to the benefit of this Section 3(a), the
Issuer shall use its reasonable best efforts to keep any Registration Statement
required by this Section 3(a) continuously effective, supplemented, amended and
current as required by and subject to the provisions of Section 4(a) hereof and
in conformity with the requirements of this Agreement, the Act and the policies,
rules

                                       2
<PAGE>

and regulations of the Commission as announced from time to time, until
the earlier of (A) the Expiration Date and (B) the first date as of which (i)
all Warrants have been exercised pursuant to the Registration Statement or (ii)
all Warrant Shares (other than Warrant Shares issued upon exercise of a Warrant
in accordance with a Registration Statement) have been disposed of by the
Holders thereof pursuant to such Registration Statement or distributed to the
public pursuant to Rule 144 under the Act; provided that such obligation shall
expire before such date if the Issuer delivers to the Warrant Agent a written
opinion of counsel to the Issuer (which opinion of counsel shall be reasonably
satisfactory to the Warrant Agent) that all Holders (other than Affiliates of
the Issuer) of Warrants and Warrant Shares may resell the Warrants and the
Warrant Shares without registration under the Act and without restriction as to
the manner, timing or volume of any such sale (such period, the "Effectiveness
                                                                 -------------
Period"); and provided, further, that notwithstanding the foregoing, any
------
Affiliate of the Issuer may, with notice to the Issuer, require the Issuer to
keep the Registration Statement continuously effective for resales by such
Affiliate for so long as such Affiliate holds Warrants or Warrant Shares,
including as a result of any market-making activities or other trading
activities of such Affiliate.  Notwithstanding the foregoing, the Issuer shall
not be required to amend or supplement the Registration Statement, any related
prospectus or any document incorporated therein by reference, for a period (a

"Black Out Period") not to exceed, for so long as this Agreement is in effect,
-----------------
60 consecutive days and no more than two times in any calendar year, in the
event that (i) an event or circumstance occurs and is continuing as a result of
which the Registration Statement, any related prospectus or any document
incorporated therein by reference as then amended or supplemented or proposed to
be filed would, in the good faith judgment of the Issuer, contain an untrue
statement of a material fact or omit to state a material fact necessary in order
to make the statements therein, in the light of the circumstances under which
they were made, not misleading, and (ii)(A) the Issuer determines in its good
faith judgment that the disclosure of such event at such time could reasonably
be expected to  have a material adverse effect on the business or operations of
the Issuer or (B) the disclosure otherwise relates to a material business
transaction or development which has not yet been publicly disclosed; provided
that such Black Out Period shall be extended for any period, not to exceed an
aggregate of 45 days in any calendar year, during which the Commission is
reviewing any proposed amendment or supplement to the Registration Statement,
any related prospectus or any document incorporated therein by reference which
has been filed by the Issuer; and provided, further, that no Black Out Period
may be in effect during the three months prior to the Expiration Date.

     (b) Provision by Holders of Certain Information in Connection with the
         ------------------------------------------------------------------
Registration Statement.  No Holder of Transfer Restricted Securities may include
----------------------
any of its Transfer Restricted Securities in any Registration Statement pursuant
to this Agreement unless and until such Holder furnishes to the Issuer in
writing, within 20 days after receipt of a request therefor, the information
specified in Item 507 or 508 of Regulation S-K, as applicable, of the Act for
use in connection with any Registration Statement or Prospectus or preliminary
Prospectus included therein.  No Holder of Transfer Restricted Securities shall
be entitled to Liquidated Damages pursuant to Section 8 unless and until such
Holder shall have provided all such information in the time period specified
above and the Issuer shall have a period of five Business Days after the end of
such 20 day period to include such information in any Shelf Registration
Statement or Prospectus or preliminary Prospectus included therein.  Each
selling Holder agrees to promptly furnish additional information required to be
disclosed in order to make the information previously furnished to the Issuer by
such Holder not misleading.

                                       3
<PAGE>

SECTION 4.  REGISTRATION PROCEDURES

     (a)  In connection with the Registration Statement and any related
Prospectus required by this Agreement, the Issuer shall:

          (i)   use its reasonable best efforts to effect such registration in
     accordance with Section 3 and in accordance with the intended method or
     methods of distribution thereof (as indicated in the information furnished
     to the Issuer pursuant to Section 3(b) hereof), and pursuant thereto the
     Issuer will prepare and file with the Commission a Registration Statement
     relating to the registration on any appropriate form under the Act, which
     form shall be available for the registration referenced in Section 3 and in
     accordance with the intended method or methods of distribution thereof
     within the time periods and otherwise in accordance with the provisions
     hereof;

          (ii)  use its reasonable best efforts to keep such Registration
     Statement continuously effective and provide all requisite financial
     statements for the period specified in Section 3 of this Agreement.  Upon
     the occurrence of any event or circumstance that would cause any such
     Registration Statement or the Prospectus contained therein (A) to contain
     an untrue statement of material fact or omit to state any material fact
     necessary to make the statements therein, in the light of the circumstances
     under which they were made, not misleading or (B) not to be effective and
     usable for resale of Transfer Restricted Securities during the period
     required by this Agreement, the Issuer shall, subject to Section 3(a), file
     promptly, subject to Section 4(a)(vi), an appropriate amendment to such
     Registration Statement or a supplement to the Prospectus, as applicable,
     curing such defect, and, in the case of an amendment, use its reasonable
     best efforts to cause such amendment to be declared effective as soon as
     practicable;

          (iii)  prepare and file with the Commission such amendments and post-
     effective amendments to the applicable Registration Statement as may be
     necessary to keep such Registration Statement effective for the applicable
     period set forth in Section 3; cause the Prospectus to be supplemented by
     any required Prospectus supplement, and as so supplemented to be filed
     pursuant to Rule 424 under the Act, and to comply fully with Rules 424,
     430A and 462, as applicable, under the Act in a timely manner; and comply
     with the provisions of the Act with respect to the disposition of all
     securities covered by such Registration Statement during the applicable
     period in accordance with the intended method or methods of distribution by
     the sellers thereof set forth in such Registration Statement or supplement
     to the Prospectus;

          (iv)  advise the Holders named in any Shelf Registration Statement and
     the Initial Purchasers promptly and, if requested by any of such Persons,
     confirm such advice in writing, (A) when the Prospectus or any Prospectus
     supplement or post-effective amendment has been filed, and, with respect to
     any applicable Registration Statement or any post-effective amendment
     thereto, when the same has become effective, (B) of any request by the
     Commission for amendments to the Registration Statement or amendments or
     supplements to the Prospectus or for additional information relating
     thereto, (C) of the issuance by the Commission of any stop order suspending
     the effectiveness of the Registration Statement under the Act or of the
     suspension by any state securities

                                       4
<PAGE>

     commission of the qualification of the Transfer Restricted Securities for
     offering or sale in any jurisdiction, or the initiation of any proceeding
     for any of the preceding purposes, and (D) of the happening of any event or
     circumstance that as a result of which the Registration Statement, any
     related prospectus or any document incorporated therein by reference as
     then amended or supplemented or proposed to be filed would, in the Issuer's
     good faith judgment, contain an untrue statement of a material fact or omit
     to state a material fact necessary in order to make the statements therein,
     in the light of the circumstances under which they were made, not
     misleading. If at any time the Commission shall issue any stop order
     suspending the effectiveness of the Registration Statement, or any state
     securities commission or other regulatory authority shall issue an order
     suspending the qualification or exemption from qualification of the
     Transfer Restricted Securities under state securities or Blue Sky laws, the
     Issuer shall use its reasonable best efforts to obtain the withdrawal or
     lifting of such order at the earliest possible time;

          (v)    subject to Section 4(a)(ii), if any event or circumstance
     contemplated by Section 4(a)(iv)(D) hereof shall exist or have occurred,
     prepare a supplement or post-effective amendment to the Registration
     Statement or related Prospectus or any document incorporated therein by
     reference or file any other required document so that, as thereafter
     delivered to the purchasers of Transfer Restricted Securities, the
     Prospectus will not contain an untrue statement of a material fact or omit
     to state any material fact necessary to make the statements therein, in the
     light of the circumstances under which they were made, not misleading;

          (vi)   furnish to counsel to the Holders named in any Shelf
     Registration Statement and the Initial Purchasers, before filing with the
     Commission, copies of any Registration Statement or any Prospectus included
     therein or any amendments or supplements to any such Registration Statement
     or Prospectus (including all documents incorporated by reference after the
     initial filing of such Registration Statement), which documents will be
     subject to the review and comment of such counsel for a period of at least
     five Business Days, and the Issuer will not file any such Registration
     Statement or Prospectus or any amendment or supplement to any such
     Registration Statement or Prospectus (including all such documents
     incorporated by reference) to which such counsel shall reasonably object
     within five Business Days after the receipt thereof. Such counsel shall be
     deemed to have reasonably objected to such filing if such Registration
     Statement, amendment, Prospectus or supplement, as applicable, as proposed
     to be filed, contains an untrue statement of a material fact or omits to
     state any material fact necessary to make the statements therein, in the
     light of the circumstances under which they were made, not misleading or
     fails to comply with the applicable requirements of the Act;

          (vii)  promptly prior to the filing of any document (other than any
     document relative to the ordinary course of the Issuer's business) that is
     to be incorporated by reference into a Registration Statement or
     Prospectus, provide copies of such document to counsel to the Holders named
     in any Shelf Registration Statement and the Initial Purchasers, make the
     Issuer's representatives available for discussion of such document

                                       5
<PAGE>

     and other customary due diligence matters, and include such information in
     such document prior to the filing thereof as the Initial Purchasers may
     reasonably request;

          (viii) make available, at reasonable times, for inspection by the
     Holders named in any Shelf Registration Statement and the Initial
     Purchasers and any attorney or accountant retained by such Persons, all
     financial and other records, pertinent corporate documents of the Issuer
     and cause the Issuer's officers, directors and employees to supply all
     information reasonably requested by the Initial Purchasers, attorney or
     accountant in connection with such Registration Statement or any post-
     effective amendment thereto subsequent to the filing thereof and prior to
     its effectiveness;

          (ix)   if requested by the Holders named in any Shelf Registration
     Statement and the Initial Purchasers, promptly include in any Registration
     Statement or Prospectus, pursuant to a supplement or post-effective
     amendment if necessary, such information as such Persons may reasonably
     request to have included therein, including, without limitation,
     information relating to the plan of distribution (the "Plan of
                                                            -------
     Distribution") of the Transfer Restricted Securities and the use of the
     ------------
     Registration Statement or Prospectus for market-making activities; and make
     all required filings of such Prospectus supplement or post-effective
     amendment as soon as practicable after the Issuer is notified of the
     matters to be included in such Prospectus supplement or post-effective
     amendment;

          (x)    furnish to the Initial Purchasers and each Holder named in any
     Shelf Registration Statement upon request, without charge, at least one
     copy of the Registration Statement, as first filed with the Commission, and
     of each amendment thereto, including all documents incorporated by
     reference therein and all exhibits (excluding exhibits incorporated therein
     by reference);

          (xi)   deliver to the Initial Purchasers and each Holder named in any
     Shelf Registration Statement, without charge, as many copies of the
     Prospectus (including each preliminary prospectus) and any amendment or
     supplement thereto as the Initial Purchasers or such Holder reasonably may
     request; the Issuer hereby consents to the use (in accordance with law and
     subject to Section 4(b) hereof) of the Prospectus and any amendment or
     supplement thereto by each selling Person in connection with the offering
     and the sale of the Transfer Restricted Securities covered by the
     Prospectus or any amendment or supplement thereto and all market-making
     activities of the Initial Purchasers, as the case may be;

          (xii)  upon the request of DLJ or any successor entity thereto, enter
     into such customary agreements (including customary underwriting
     agreements) and make such customary representations and warranties and take
     all such other actions in connection therewith in order to expedite or
     facilitate the disposition of the Transfer Restricted Securities pursuant
     to any applicable Registration Statement contemplated by this Agreement as
     may be reasonably requested by DLJ or such successor entity in connection
     with any sale or resale pursuant to any applicable Registration Statement.
     In such connection, the Issuer shall:

                                       6
<PAGE>

               (A)  upon request of DLJ or its successor entity, furnish (or in
          the case of paragraphs (2) and (3), use its reasonable best efforts to
          cause to be furnished) to DLJ or its successor entity, upon the
          effectiveness of the Registration Statement:

                    (1) a certificate, dated such date, signed on behalf of the
               Issuer by (x) the President or any Vice President and (y) a
               principal financial or accounting officer of the Issuer, in
               customary form and covering matters of the type customarily
               covered in such documents provided to underwriters in connection
               with underwritten offerings;

                    (2) an opinion, dated the date of effectiveness of the
               Registration Statement, of counsel for the Issuer in customary
               form and covering matters of the type customarily covered in such
               documents provided to underwriters in connection with
               underwritten offerings; and

                    (3) a  customary comfort letter, dated the date of
               effectiveness of the Registration Statement, from the Issuer's
               independent accountants, in the customary form and covering
               matters of the type customarily covered in comfort letters to
               underwriters in connection with underwritten offerings; and

               (B)  deliver such other documents and certificates as may be
          reasonably requested by the Initial Purchasers to evidence compliance
          with the matters referred to above and with any customary conditions
          contained in any agreement entered into by the Issuer pursuant to this
          clause;

          (xiii) prior to any public offering of Transfer Restricted
     Securities, cooperate with the selling Holders and their counsel in
     connection with the registration and qualification of the Transfer
     Restricted Securities under the securities or Blue Sky laws of such
     jurisdictions as the selling Holders may reasonably request and do any and
     all other acts or things reasonably necessary or advisable to enable the
     disposition in such jurisdictions of the Transfer Restricted Securities
     covered by the applicable Registration Statement; provided that the Issuer
     shall not be required to register or qualify as a foreign corporation where
     it is not now so qualified or to take any action that would subject it to
     the service of process in suits or to taxation, other than as to matters
     and transactions relating to the Registration Statement, in any
     jurisdiction where it is not now so subject;

          (xiv)  in connection with any sale of Transfer Restricted Securities
     that will result in such securities no longer being Transfer Restricted
     Securities, cooperate with the Holders to facilitate the timely preparation
     and delivery of certificates representing Transfer Restricted Securities to
     be sold and not bearing any restrictive legends; and to register such
     Transfer Restricted Securities in such denominations and such names as the
     selling Holders may reasonably request at least two Business Days prior to
     such sale of Transfer Restricted Securities;

                                       7
<PAGE>

          (xv)   use its reasonable best efforts to cause the disposition of the
     Transfer Restricted Securities covered by the Registration Statement to be
     registered with or approved by such other governmental agencies or
     authorities as may be necessary to enable the seller or sellers thereof to
     consummate the disposition of such Transfer Restricted Securities, subject
     to the proviso contained in clause (xiii) above;

          (xvi)  provide a CUSIP number for all Transfer Restricted Securities
     not later than the effective date of a Registration Statement covering such
     Transfer Restricted Securities and provide the Warrant Agent or the
     Transfer Agent and Registrar for the Warrant Shares, as applicable, with
     printed certificates for the Transfer Restricted Securities which are in a
     form eligible for deposit with The Depository Trust Company;

          (xvii)  otherwise use its reasonable best efforts to comply with all
     applicable rules and regulations of the Commission, and make generally
     available to its security holders with regard to any applicable
     Registration Statement, as soon as practicable, a consolidated earnings
     statement meeting the requirements of Rule 158 (which need not be audited)
     covering a twelve-month period beginning after the effective date of the
     Registration Statement (as such term is defined in Rule 158(c) under the
     Act); and

          (xviii) provide promptly to the Initial Purchasers, upon request,
     each document filed with the Commission pursuant to the requirements of
     Section 13 or Section 15(d) of the Exchange Act.

     (b)  Restrictions on Holders.  Each Holder agrees by acquisition of a
          -----------------------
Transfer Restricted Security and the Initial Purchasers agree that, upon receipt
of the notice from the Issuer of the commencement of a Black Out Period (in each
case, a "Black Out Notice"), such Person will forthwith discontinue disposition
         ----------------
of Transfer Restricted Securities pursuant to the applicable Registration
Statement until such Person is advised in writing by the Issuer of the
termination of the Black Out Period.  Each Person receiving a Black Out Notice
hereby agrees that it will either (i) destroy any Prospectuses, other than
permanent file copies, then in such Person's possession which have been replaced
by the Issuer with more recently dated Prospectuses or (ii) deliver to the
Issuer (at the Issuer's expense) all copies, other than permanent file copies,
then in such Person's possession of the Prospectus covering such Transfer
Restricted Securities that was current at the time of receipt of the Black Out
Notice.

SECTION 5.  REGISTRATION EXPENSES

     All expenses incident to the Issuer's performance of or compliance with
this Agreement will be borne by the Issuer, regardless of whether a Registration
Statement becomes effective, including, without limitation: (i) all registration
and filing fees and expenses; (ii) all fees and expenses of compliance with
federal securities and state Blue Sky or securities laws; (iii) all expenses of
printing, including printing Prospectuses (whether for sales, market-making or
otherwise), messenger and delivery services and telephone; (iv) all fees and
disbursements of counsel for the Issuer; (v) if the Common Stock shall then be
listed on any national securities exchange or automated quotation system, all
application and filing fees in connection with listing the Warrant Shares
thereon, and (vi) all fees and disbursements of independent certified public

                                       8
<PAGE>

accountants of the Issuer (including the expenses of any special audit and
comfort letters required by or incident to such performance).

     The Issuer will, in any event, bear its internal expenses (including,
without limitation, all salaries and expenses of its officers and employees
performing legal or accounting duties), the expenses of any annual audit and the
fees and expenses of any Person, including special experts, retained by the
Issuer.

SECTION 6.  INDEMNIFICATION

     (a) The Issuer agrees to indemnify and hold harmless each Holder, its
directors, officers and each Person, if any, who controls such Holder (within
the meaning of Section 15 of the Act or Section 20 of the Exchange Act), from
and against any and all losses, claims, damages, liabilities, judgments,
(including, without limitation, any reasonable legal or other expenses incurred
in connection with investigating or defending any matter, including any action
that could give rise to any such losses, claims, damages, liabilities or
judgments) caused by any untrue statement or alleged untrue statement of a
material fact contained in any Registration Statement, preliminary prospectus or
Prospectus (or any amendment or supplement thereto) provided by the Issuer to
any Holder or any prospective purchaser of Transfer Restricted Securities, or
caused by any omission or alleged omission to state therein a material fact
required to be stated therein or necessary to make the statements therein not
misleading, except insofar as such losses, claims, damages, liabilities or
judgments are caused by an untrue statement or omission or alleged untrue
statement or omission that is based upon information relating to any of the
Holders furnished in writing to the Issuer by or on behalf of the Holders,

provided further, that the Issuer shall not be liable to any Holder or any of
-------- -------
such Holder's directors, officers and Persons controlling such Holder with
respect to any preliminary prospectus to the extent that any such losses,
claims, damages, liabilities or judgments of such Person results proximately and
primarily from the fact that such Person sold Transfer Restricted Securities to
a second Person to whom there was not sent or given, at or before the written
confirmation of such sale, a copy of the Prospectus (excluding documents
incorporated by reference) if the Issuer has previously furnished copies thereof
to such first Person in compliance with this Agreement and the losses, claims,
damages, liabilities or judgments of such first Person results proximately and
primarily from an untrue statement or omission of a material fact contained in
such preliminary prospectus which was corrected in the Prospectus (or the
Prospectus as then amended or supplemented).

     (b) Each Holder of Transfer Restricted Securities agrees, severally and not
jointly, to indemnify and hold harmless the Issuer, its directors and officers,
and each person, if any, who controls (within the meaning of Section 15 of the
Act or Section 20 of the Exchange Act) the Issuer, to the same extent as the
foregoing indemnity from the Issuer set forth in Section 6(a) hereof, but only
with reference to information relating to such Holder furnished in writing to
the Issuer by or on behalf of such Holder expressly for use in any Registration
Statement.  In no event shall any Holder, its directors, officers or any Person
who controls such Holder be liable or responsible for any amount in excess of
the amount by which the total amount received by such Holder with respect to its
sale of Transfer Restricted Securities pursuant to a Registration Statement
exceeds (i) the amount paid by such Holder for such Transfer Restricted
Securities and (ii) the amount of any damages that such Holder, its directors,
officers or any Person who

                                       9
<PAGE>

controls such Holder has otherwise been required to pay by reason of such untrue
or alleged untrue statement or omission or alleged omission.

     (c) In case any action shall be commenced involving any person in respect
of which indemnity may be sought pursuant to Section 6(a) or 6(b) (the

"indemnified party"), the indemnified party shall promptly notify the person
------------------
against whom such indemnity may be sought (the "indemnifying party") in writing,
                                                ------------------
and the indemnifying party shall assume the defense of such action, including
the employment of counsel reasonably satisfactory to the indemnified party and
the payment of all fees and expenses of such counsel, as incurred (except that,
in the case of any action in respect of which indemnity may be sought pursuant
to both Sections 6(a) and 6(b), a Holder shall not be required to assume the
defense of such action pursuant to this Section 6(c), but may employ separate
counsel and participate in the defense thereof, but the fees and expenses of
such counsel, except as provided below, shall be at the expense of the Holder).
Any indemnified party shall have the right to employ separate counsel in any
such action and participate in the defense thereof, but the fees and expenses of
such counsel shall be at the expense of the indemnified party, unless (i) the
employment of such counsel shall have been specifically authorized in writing by
the indemnifying party, (ii) the indemnifying party shall have failed to assume
the defense of such action or employ counsel reasonably satisfactory to the
indemnified party or (iii) the named parties to any such action (including any
impleaded parties) include both the indemnified party and the indemnifying
party, and the indemnified party shall have been advised by such counsel that
there may be one or more legal defenses available to it which are different from
or additional to those available to the indemnifying party (in which case the
indemnifying party shall not have the right to assume the defense of such action
on behalf of the indemnified party).  In any such case, the indemnifying party
shall not, in connection with any one action or separate but substantially
similar or related actions in the same jurisdiction arising out of the same
general allegations or circumstances, be liable for the fees and expenses of
more than one separate firm of attorneys (in addition to any local counsel) for
all indemnified parties and all such fees and expenses shall be reimbursed as
they are incurred.  Such firm shall be designated in writing by a majority of
the Holders, in the case of the parties indemnified pursuant to Section 6(a),
and by the Issuer, in the case of parties indemnified pursuant to Section 6(b).
The indemnifying party shall indemnify and hold harmless the indemnified party
from and against any and all losses, claims, damages, liabilities and judgments
by reason of any settlement of any action (i) effected with its written consent
or (ii) effected without its written consent if the settlement is entered into
more than twenty business days after the indemnifying party shall have received
a request from the indemnified party for reimbursement for the fees and expenses
of counsel (in any case where such fees and expenses are at the expense of the
indemnifying party) and, prior to the date of such settlement, the indemnifying
party shall have failed to comply with such reimbursement request.   No
indemnifying party shall, without the prior written consent of the indemnified
party, effect any settlement or compromise of, or consent to the entry of
judgment with respect to, any pending or threatened action in respect of which
the indemnified party is or could have been a party and indemnity or
contribution may be or could have been sought hereunder by the indemnified
party, unless such settlement, compromise or judgment (i) includes an
unconditional release of the indemnified party from all liability on claims that
are or could have been the subject matter of such action and (ii) does not
include a statement as to or an admission of fault, culpability or a failure to
act, by or on behalf of the indemnified party.

                                       10
<PAGE>

     (d) To the extent that the indemnification provided for in this Section 6
is unavailable to an indemnified party in respect of any losses, claims,
damages, liabilities or judgments referred to herein, then each indemnifying
party, in lieu of indemnifying such indemnified party, shall contribute to the
amount paid or payable by such indemnified party as a result of such losses,
claims, damages, liabilities or judgments (i) in such proportion as is
appropriate to reflect the relative benefits received by the Issuer, on the one
hand, and the Holders, on the other hand, from their sale of Transfer Restricted
Securities or (ii) if the allocation provided by clause 6(d)(i) is not permitted
by applicable law, in such proportion as is appropriate to reflect not only the
relative benefits referred to in clause 6(d)(i) hereof but also the relative
fault of the Issuer, on the one hand, and of the Holder, on the other hand, in
connection with the statements or omissions which resulted in such losses,
claims, damages, liabilities or judgments, as well as any other relevant
equitable considerations.  The relative fault of the Issuer, on the one hand,
and of the Holder, on the other hand, shall be determined by reference to, among
other things, whether the untrue or alleged untrue statement of a material fact
or the omission or alleged omission to state a material fact relates to
information supplied by the Issuer, on the one hand, or by or on behalf of the
Holder, on the other hand, and the parties' relative intent, knowledge, access
to information and opportunity to correct or prevent such statement or omission.
The amount paid or payable by an indemnified party as a result of the losses,
claims, damages, liabilities or judgments referred to above shall be deemed to
include, subject to the limitations set forth in Section 6(a), any legal or
other fees or expenses reasonably incurred by such indemnified party in
connection with investigating or defending any matter, including any action that
could have given rise to such losses, claims, damages, liabilities or judgments.

     The Issuer and each Holder agree that it would not be just and equitable if
contribution pursuant to this Section 6(d) were determined by pro rata
allocation (even if the Holders were treated as one entity for such purpose) or
by any other method of allocation which does not take account of the equitable
considerations referred to in the immediately preceding paragraph.
Notwithstanding the provisions of this Section 6, no Holder, its directors, its
officers or any Person, if any, who controls such Holder shall be required to
contribute, in the aggregate, any amount in excess of the amount by which the
total received by such Holder with respect to the sale of Transfer Restricted
Securities pursuant to a Registration Statement exceeds (i) the amount paid by
such Holder for such Transfer Restricted Securities and (ii) the amount of any
damages which such Holder has otherwise been required to pay by reason of such
untrue or alleged untrue statement or omission or alleged omission.  No person
guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of
the Act) shall be entitled to contribution from any person who was not guilty of
such fraudulent misrepresentation.  The Holders' obligations to contribute
pursuant to this Section 6(d) are several in proportion to the respective
principal amount of Transfer Restricted Securities held by each Holder hereunder
and not joint.

     (e) The Issuer agrees that the cross indemnity and contribution provisions
of this Section 6 shall apply to the Initial Purchasers to the same extent, on
the same conditions, as it applies to Holders.

SECTION 7.  RULE 144

     The Issuer agrees with each Holder, for so long as any Transfer Restricted
Securities remain outstanding and during any period in which the Issuer is
subject to Section 13 or 15(d) of

                                       11
<PAGE>

the Exchange Act, to make all filings required thereby in a timely manner in
order to permit resales of such Transfer Restricted Securities pursuant to Rule
144.

SECTION 8.  LIQUIDATED DAMAGES

     (a)  Liquidated Damages. The Issuer and the Initial Purchasers agree that
          ------------------
the Holders will suffer damages if the Issuer fails to fulfill its obligations
pursuant to Section 3 and 4 of this Agreement and that it would not be possible
to ascertain the extent of such damages.  Accordingly, in the event of such
failure by the Issuer to fulfill such obligations, the Issuer hereby agrees to
pay liquidated damages ("Liquidated Damages") to each Holder entitled to
                         ------------------
Liquidated Damages under the circumstances and to the extent set forth below:

          (i)    if the Registration Statement has not been filed with the
     Commission within 90 days after the Closing Date;

          (ii)   if the Issuer has not used its reasonable best efforts to have
     the Registration Statement declared effective by the Commission within 180
     days after the Closing Date; or

          (iii)  if the Registration Statement has been declared effective by
     the Commission and such Registration Statement ceases to be effective
     during the Effectiveness Period, (other than during a Black Out Period),
     without being succeeded on the same day immediately by a post-effective
     amendment to such Registration Statement that cures such failure and that
     is itself immediately declared effective on the same day, (any of the
     foregoing, a "Registration Default");
                   --------------------

then the Issuer shall pay Liquidated Damages to each Holder of a Warrant that is
a Transfer Restricted Security in an amount equal to $0.03 per week per Warrant
that is a Transfer Restricted Security held by such Holder for each week or
portion thereof that the Registration Default continues for the first 90-day
period immediately following the occurrence of such Registration Default.  This
amount will increase by an additional $0.02 per week per Warrant with respect to
each subsequent 90-day period, up to a maximum amount of Liquidated Damages
equal to $0.07 per week per Warrant. The provision for Liquidated Damages will
continue until such Registration Default has been cured. The Issuer will not be
required to pay Liquidated Damages for more than one Registration Default at any
given time.  A Registration Default under clause (i) above shall be cured on the
date that the Registration Statement is filed with the Commission; a
Registration Default under clause (ii) above shall be cured on the date that the
Registration Statement is declared effective by the Commission; a Registration
Default under clause (iii) above shall be cured on the earlier of (A) the date
that the post-effective amendment curing the deficiency in the Registration
Statement is declared effective or (B) the Effectiveness Period expires.
Notwithstanding the foregoing, the Issuer shall not be deemed to have failed to
perform its obligations under clauses (i) through (iii) above by the reason of
the failure of any Holder to provide information regarding itself reasonably
requested by the Issuer or any regulatory agency having jurisdiction over any of
the Holders at least 10 business days prior to a Registration Default.

                                       12
<PAGE>

     (b) Payment of Liquidated Damages.  The Issuer shall notify the Warrant
         -----------------------------
Agent within one Business Day after each and every date on which a Registration
Default occurs (an "Event Date").  Liquidated Damages shall accrue from the date
                    ----------
of the Registration Default.  Liquidated Damages accrued as of January 15 or
July 15 of each year (each a "Payment Date") will be payable on such Payment
                              ------------
Date.  The Issuer shall pay Liquidated Damages on the applicable Payment Date to
the Persons who are Holders of Warrants that are entitled to receive Liquidated
Damages at the close of business on January 1 or July 1 next preceding the
Payment Date.  In the case of Warrants held through The Depositary Trust Company
("DTC"), Liquidated Damages shall be payable to DTC by wire transfer of
  ---
immediately available funds.  In the case of Warrants held in certificated form,
Liquidated Damages shall be payable at the office of the Warrant Agent or, at
the option of the Issuer, payment of Liquidated Damages may be made by check
mailed to the Holders that are entitled to receive Liquidated Damages at their
addresses set forth in the register of Holders, provided that payment by wire
transfer of immediately available funds shall be required with respect to the
Liquidated Damages on all such Warrants the Holders of which shall have provided
written wire transfer instructions to the Issuer and the Warrant Agent.  Such
payment shall be in such coin or currency of the United States of America as at
the time of payment is legal tender for payment of public and private debts.

SECTION 9.  MISCELLANEOUS

     (a) Remedies.  The Issuer acknowledges and agrees that any failure by the
         --------
Issuer to comply with its obligations under Section 3 hereof may result in
material irreparable injury to the Initial Purchasers or the Holders for which
there is no adequate remedy at law, that it will not be possible to measure
damages for such injuries precisely and that, in the event of any such failure,
the Initial Purchasers or any Holder may obtain such relief as may be required
to specifically enforce the Issuer's obligations under Section 3 hereof.  The
Issuer further agrees to waive the defense in any action for specific
performance that a remedy at law would be adequate.

     (b) No Inconsistent Agreements.  The Issuer will not, on or after the date
         --------------------------
of this Agreement, enter into any agreement with respect to its securities that
is inconsistent with the rights granted to the Holders in this Agreement or
otherwise conflicts with the provisions hereof.  Except as set forth in the
Offering Memorandum, the Issuer has not previously entered into any agreement
granting any registration rights with respect to its securities to any Person.
The rights granted to the Holders hereunder do not in any way conflict with and
are not inconsistent with the rights granted to the holders of the Issuer's
securities under any agreement in effect on the date hereof.

     (c) Amendments and Waivers.  The provisions of this Agreement may not be
         ----------------------
amended, modified or supplemented, and waivers or consents to or departures from
the provisions hereof may not be given unless (i) in the case of this Section
9(c)(i), the Issuer has obtained the written consent of Holders of all
outstanding Transfer Restricted Securities, and (ii) in the case of all other
provisions hereof, the Issuer has obtained the written consent of Holders of a
majority of the outstanding Transfer Restricted Securities (excluding Transfer
Restricted Securities held by the Issuer or its Affiliates); provided that this
Agreement may be amended without the consent of any Holder in order to cure any
ambiguity or to correct or supplement any provision contained herein which may
be defective or inconsistent with any other provision herein, or to make any
other provisions in regard to matters or questions arising hereunder which

                                       13
<PAGE>

the Issuer may deem necessary or desirable and which shall not in any way
adversely affect any Holder.

     (d) Third Party Beneficiary.  The Holders shall be third party
         -----------------------
beneficiaries to the agreements granting rights to Holders made hereunder
between the Issuer, on the one hand, and the Initial Purchasers, on the other
hand, and shall have the right to enforce such agreements directly to the extent
they may deem such enforcement necessary or advisable to protect its rights or
the rights of Holders hereunder.

     (e) Notices.  All notices and other communications provided for or
         -------
permitted hereunder shall be made in writing by hand-delivery, first-class mail
(registered or certified, return receipt requested), telex, telecopier, or air
courier guaranteeing overnight delivery:

          (i)  if to a Holder, at the address set forth on the records of the
     Warrant Agent, with a copy to the Warrant Agent; and

          (ii) if to the Issuer:

               IWO Holdings, Inc.
               319 Great Oaks Boulevard
               Albany, New York  12203
               Telecopier No.:  (518) 862-6001
               Attention:  President

               With copies to:

               Gibson, Dunn & Crutcher LLP
               200 Park Avenue
               47th Floor
               New York, New York  10166
               Telecopier No.:  (212) 351-4035
               Attention:   Joerg H. Esdorn

     All such notices and communications shall be deemed to have been duly
given:  at the time delivered by hand, if personally delivered; five Business
Days after being deposited in the mail, postage prepaid, if mailed; when receipt
acknowledged, if telecopied; and on the next Business Day, if timely delivered
to an air courier guaranteeing overnight delivery.

     Copies of all such notices, demands or other communications shall be
concurrently delivered by the Person giving the same to the Warrant Agent at the
address specified in Warrant Agreement.

     (f) Successors and Assigns.  This Agreement shall inure to the benefit of
         ----------------------
and be binding upon the successors and assigns of each of the parties,
including, without limitation, and without the need for an express assignment,
subsequent Holders; provided that nothing herein shall be deemed to permit any
assignment, transfer or other disposition of Transfer Restricted Securities in
violation of the terms hereof or of the Purchase Agreement or the Warrant
Agreement.  If any transferee of any Holder shall acquire Transfer Restricted
Securities in any

                                       14
<PAGE>

manner, whether by operation of law or otherwise, such Transfer Restricted
Securities shall be held subject to all of the terms of this Agreement, and by
taking and holding such Transfer Restricted Securities such Person shall be
conclusively deemed to have agreed to be bound by and to perform all of the
terms and provisions of this Agreement, including the restrictions on resale set
forth in this Agreement and, if applicable, the Purchase Agreement or Warrant
Agreement, as the case may be, and such Person shall be entitled to receive the
benefits hereof.

     (g) Counterparts.  This Agreement may be executed in any number of
         ------------
counterparts and by the parties hereto in separate counterparts, each of which
when so executed shall be deemed to be an original and all of which taken
together shall constitute one and the same agreement.

     (h) Headings.  The headings in this Agreement are for convenience of
         --------
reference only and shall not limit or otherwise affect the meaning hereof.

     (i) Governing Law.  THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
         -------------
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO THE
CONFLICT OF LAW RULES THEREOF.

     (j) Severability.  In the event that any one or more of the provisions
         ------------
contained herein, or the application thereof in any circumstance, is held
invalid, illegal or unenforceable, the validity, legality and enforceability of
any such provision in every other respect and of the remaining provisions
contained herein shall not be affected or impaired thereby.

     (k) Entire Agreement.  This Agreement is intended by the parties as a final
         ----------------
expression of their agreement and intended to be a complete and exclusive
statement of the agreement and understanding of the parties hereto in respect of
the subject matter contained herein.  There are no restrictions, promises,
warranties or undertakings, other than those set forth or referred to herein
with respect to the registration rights granted with respect to the Transfer
Restricted Securities.  This Agreement supersedes all prior agreements and
understandings between the parties with respect to such subject matter.

                  [remainder of page intentionally left blank]

                                       15
<PAGE>

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
first written above.

                                   IWO HOLDINGS, INC.

                                   By:  /s/ Steven M. Nielsen
                                   ---------------------
                                   Name:  Steven M. Nielsen
                                   Title: Chief Executive Officer

DONALDSON, LUFKIN & JENRETTE SECURITIES
 CORPORATION

By:  /s/ William L. Spiro
     --------------------
     Name:  William L. Spiro
     Title: Senior Vice President

CHASE SECURITIES INC.

By:  /s/ Jessica Laxman
     ------------------
     Name:  Jessica Laxman
     Title: Vice President

BNP PARIBAS SECURITIES CORP.

By:  /s/ Douglas Cook
     ----------------
     Name:  Douglas Cook
     Title: Director

UBS WARBURG LLC

By:  /s/ Dominic Lester
     ------------------
     Name:  Dominic Lester
     Title: Executive Director

By:  /s/ F. Davis Terry, Jr.
     -----------------------
     Name:  F. Davis Terry, Jr.
     Title: Executive Director