SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                                    FORM 8-K

                                 CURRENT REPORT

     Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

                                November 5, 2003
                               -------------------
                Date of Report (Date of earliest event reported)
                               -------------------

                                  iBASIS, INC.
                              ---------------------
               (Exact Name of Registrant as Specified in Charter)


              DELAWARE                    0-27127          04-3332534
    ------------------------------     --------------    -----------------------
   (State or Other Jurisdiction of      (Commission        (IRS Employer
           Incorporation)               File Number)     Identification No.)



                     20 Second Avenue, Burlington, MA 01803
            ---------------------------------------------------------
               (Address of Principal Executive Offices) (Zip Code)

                                 (781) 505-7500

              (Registrant's telephone number, including area code)
                                 ---------------




Item 7.  Financial Statements, Pro Forma Financial Information and Exhibits.

         (c)      Exhibits.

                  Exhibit
                  Number            Description
                  ------------      -----------
                  Exhibit 99.1      Press Release, dated November 5, 2003


Item 9.  Regulation and Disclosure.

     On November 5, 2003, iBasis, Inc. (the "Company") issued a press release
regarding results for the three months ended September 30, 2003. A copy of this
press release is being furnished as Exhibit 99.1 to this Current Report on Form
8-K. This Current Report on Form 8-K and the press release attached hereto are
being furnished by the Company pursuant to Item 12 of Form 8-K, insofar as they
disclose historical information regarding the Company's results of operations
for the three months ended September 30, 2003. In accordance with General
Instruction B.6 of Form 8-K, the information in this Current Report on Form 8-K,
including Exhibit 99.1, shall not be deemed "filed" for the purposes of Section
18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to
the liability of that section, nor shall it be deemed incorporated by reference
in any filing under the Securities Act of 1933, as amended, except as shall be
expressly set forth by specific reference in such a filing.


                                    SIGNATURE

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

Date:  November 5, 2003        iBasis, INC.

                               By:  /s/      Richard Tennant
                                    --------------------------------------------
                                    Vice President, Finance and Administration
                                    And Chief Financial Officer
                                    (Principal Financial and Accounting Officer)