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                                                                     Exhibit 4.3


                             PRICEINTERACTIVE, INC.
                        RESTRICTED STOCK AWARD AGREEMENT


         This Restricted Stock Award Agreement (this "AGREEMENT"), dated as of
_______ (the "AWARD DATE"), is by and between PriceInteractive, Inc., a Delaware
corporation (the "CORPORATION"), and __________ (the "PARTICIPANT"), an employee
of the Corporation.

         1. AWARD OF RESTRICTED STOCK. Subject to the provisions of the
PriceInteractive, Inc. Amended and Restated 2000 Restricted Stock Plan (the
"PLAN") and this Agreement, the Corporation hereby grants to the Participant
_______ shares (the "AWARD") of the Corporation's Class A Common Stock, par
value $0.01 per share (the "CLASS A COMMON STOCK"), to which the conditions
referred to in Section 2.16 of the Plan attach (the "RESTRICTED STOCK"). The
Award evidenced by this Agreement shall be effective if and only if the merger
(the "MERGER") of the Corporation with and into a subsidiary of iBasis, Inc., a
Delaware corporation ("IBASIS"), is consummated in accordance with that certain
Agreement and Plan of Merger and Reorganization among iBasis, the Corporation
and the other parties thereto dated December 12, 2000 (the "MERGER AGREEMENT").

         2. VESTING CONDITIONS.

             (a) As used herein, "VESTING CONDITIONS" has the meaning set forth
in Section 2.16 of the Plan, a copy of which is attached as EXHIBIT A.

             (b) The Participant generally shall have the rights and privileges
of a stockholder as to the Restricted Stock, including the right to receive cash
dividends and the right to vote. However, notwithstanding any other provision
hereof, the following restrictions shall apply to the Restricted Stock: (i) the
Participant shall not be entitled to delivery of a certificate for the
Restricted Stock until the satisfaction of the Vesting Conditions; (ii)
Restricted Stock may not be sold, transferred (except by will or the laws of
descent and distribution), assigned, pledged or otherwise encumbered or disposed
of prior to satisfaction of the Vesting Conditions; (iii) except for any shares
of Restricted Stock with respect to which the Vesting Conditions have been
satisfied prior to such date, or as otherwise expressly provided herein and in
the Plan, the Participant shall forfeit and immediately transfer back to
Corporation without payment all of the Restricted Stock, and all rights of the
Participant to such Restricted Stock shall terminate without further obligation
on the part of the Corporation, if and when the Participant ceases to be an
employee of the Corporation. As a condition of the Award, the Corporation may
require the Participant to deliver to the Corporation a duly signed stock power,
endorsed in blank, with respect to the shares of Class A Common Stock subject to
the Award.

         3. SATISFACTION OF VESTING CONDITIONS. Upon the satisfaction of the
Vesting Conditions as to particular shares of Restricted Stock, the restrictions
on the applicable number of shares of Restricted Stock shall terminate, and a
stock certificate for such number of shares of Class A Common Stock shall be
delivered, free and clear of all such restrictions, to the


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Participant or, subject to Section 4, the Participant's beneficiary or estate,
as the case may be, subject to the provisions of Sections 6 and 7(e). The
Corporation shall not be required to deliver any fractional share of Class A
Common Stock, but will pay, in lieu thereof, the fair market value (as defined
in the Plan, determined as of the date the conditions terminate) of such
fractional share to the Participant or the Participant's beneficiary or estate,
as the case may be. The Corporation shall pay any original issue tax that may be
due upon the issuance of the Restricted Stock and all other costs incurred by
the Corporation in issuing such shares of Class A Common Stock.

         4. NONTRANSFERABILITY OF RESTRICTED STOCK. The Restricted Stock is not
transferable by the Participant (a) prior to the satisfaction of the Vesting
Conditions except by will or the law of descent and distribution and (b) except
following the satisfaction of the Vesting Conditions. Without limiting the
generality of the foregoing, prior to the expiration of the Vesting Conditions,
the Award and Restricted Stock may not be sold, transferred except as aforesaid,
assigned, pledged, or otherwise encumbered or disposed of, shall not be
assignable by operation of law, and shall not be subject to execution,
attachment or similar process. Any attempted sale, transfer, pledge, assignment
or other encumbrance or disposition of the Restricted Stock contrary to the
provisions hereof, or the levy of any execution, attachment or similar process
upon the Restricted Stock, shall be null and void and without effect.

         5. REORGANIZATION OR LIQUIDATION OF THE CORPORATION. In the event the
Corporation is succeeded by another corporation in a reorganization, which term
includes a merger, consolidation, acquisition of all or substantially all of the
assets or voting stock of the Corporation, or other extraordinary transaction
with similar effect, the Participant shall be entitled to receive (subject to
any required action by stockholders) such securities of the surviving or
resulting corporation or other consideration as the board of directors of such
corporation shall determine to be as nearly equivalent as practicable to the
nearest whole number and class of shares of stock or other securities or other
consideration to which the Participant would have been entitled under the terms
of such reorganization (without adjustment for any fractional interest thereby
eliminated), as if, immediately prior to such event, the Participant had been
the holder of record of the number of shares of Class A Common Stock which were
then Restricted Stock without any restriction whatsoever. Any such shares of
stock of other securities issued to the Participant in connection with any such
reorganization shall, after any such reorganization, be deemed to be Restricted
Stock for all purposes of this Agreement and the Plan. Notwithstanding the
foregoing, all shares of Restricted Stock shall convert into shares of the
Common Stock of iBasis upon the consummation of the Merger in accordance with
Section 2.5(c) of the Merger Agreement.

         6. COMPLIANCE WITH SECURITIES LAWS; LEGEND ON SHARE CERTIFICATES.

             (a) The Award and Restricted Stock have not been registered under
the Securities Act of 1933, as amended (the "SECURITIES ACT"), or under any
applicable state securities laws (the Securities Act and such state laws being
hereinafter sometimes referred to as the "SECURITIES LAWS"). The Restricted
Stock shall not be transferable except pursuant to the provisions of the
Securities Laws. The Participant represents that the Participant (i) is
acquiring the Restricted Stock for the Participant's own account and not with a
view to reselling, splitting,


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sharing or otherwise participating in a distribution thereof in violation of any
Securities Laws, (ii) understands that the effect of such representation is that
the Restricted Stock must be held indefinitely unless subsequently registered
under the Securities Laws or an exemption from such registration is available at
the time of any proposed sale or other transfer thereof, (iii) understands that
the Corporation is under no obligation to register the Restricted Stock for
resale, and (iv) is fully familiar with the circumstances under which the
Participant is required to hold the Restricted Stock and the limitations upon
transfer or other disposition thereof.

             (b) The Participant agrees that each certificate for the Restricted
Stock shall be stamped or otherwise imprinted with legends in substantially the
following forms:

                  (i) The shares represented hereby have not been registered
         under the Securities Act of 1933, as amended (the "ACT"), or under the
         state securities or blue sky laws of any state. Such shares may not be
         sold or transferred except pursuant to an effective registration
         statement under the Act or an opinion of counsel satisfactory to the
         Corporation that such registration is not required.

                  (ii) The transferability of this certificate and the shares of
         stock represented hereby are subject to the terms and conditions
         (including forfeiture) of the PriceInteractive, Inc. Amended and
         Restated 2000 Restricted Stock Plan and the applicable Award Agreement
         thereunder, as each has been assumed by iBasis. Copies of such Plan and
         agreement are on file at the offices of iBasis.

         7. MISCELLANEOUS.

             (a) NOTICES. Any notice hereunder shall be in writing, and
delivered or sent by first-class U.S. mail, postage prepaid, addressed to:

                  (i)      if to the Corporation, at:

                           PriceInteractive, Inc.
                           11800 Sunrise Valley Drive
                           Reston, VA  20191
                           Attn:   President

with a copy to:

                           iBasis, Inc.
                           20 Second Avenue
                           Burlington, MA  01803

                  (ii)     if to the Participant at:

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

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

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subject to the right of either party, by written notice hereunder, to designate
at any time hereafter some other address.

             (b) COMPLIANCE WITH LAW AND REGULATIONS. The Restricted Stock shall
be subject to all applicable Federal and state laws, rules and regulations and
to such approvals by any government or regulatory agency as may be required.
Notwithstanding any other provision of this Agreement, the restrictions on the
Restricted Stock shall not terminate or expire if such termination or expiration
would be contrary to applicable law.

             (c) NO EMPLOYMENT RIGHTS. Nothing in the Plan, this Agreement or
the award of Restricted Stock shall confer upon the Participant any rights to
continued employment with the Corporation or shall interfere with the right of
the Corporation to terminate the Participant's employment with the Corporation.

             (d) SECTION 83(B) ELECTION. If the Participant elects, in
accordance with Section 83(b) of the Internal Revenue Code of 1986, as amended
from time to time, or subsequent comparable statute (the "CODE"), to recognize
ordinary income in the year in which the Restricted Stock is awarded, the
Participant shall furnish to the Corporation a copy of a completed and signed
election form and shall pay (or make arrangements satisfactory to the
Corporation to pay) to the Corporation, within sixty (60) days after the Award
Date, any Federal, state and local taxes required to be withheld with respect to
the Award.

             (e) WITHHOLDING. Prior to the satisfaction of the Vesting
Conditions, the Participant shall make arrangements with the Corporation to pay
or otherwise satisfy any Federal, state and local tax withholding requirements
with respect to the Award. The Corporation shall, to the extent permitted by
law, have the right to deduct from any payment of any kind otherwise due to the
Participant any Federal, state and local taxes required by law to be withheld or
collected with respect to the Award.

             (f) EMPLOYMENT BY AFFILIATES. For the purpose of this Agreement,
employment by a parent or subsidiary of, or a successor to, the Corporation
shall be considered employment by the Corporation. "Subsidiary" as used herein
shall have the meaning of "subsidiary corporation" as defined in Section 424 of
the Code.

             (g) PLAN GOVERNS. The Participant hereby acknowledges receipt of a
copy of the Plan and agrees to be bound by its terms, all of which are
incorporated herein by reference. The Plan shall govern in the event of any
conflict between this Agreement and the Plan.

             (h) CHOICE OF LAW. This Agreement shall be construed in accordance
with and be governed by the laws of the State of Delaware.

             (i) COUNTERPARTS. This Agreement may be executed in two
counterparts each of which shall constitute one and the same instrument.

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         IN WITNESS WHEREOF, the parties hereto have executed and delivered this
Agreement as of the day and year first above written.

                                 PRICEINERACTIVE, INC.



                                 ----------------------------------------------
                                 By:      Daniel J. Price
                                 Title:   President and Chief Executive Officer



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                                 ---------------------------------, Participant