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

                                   FORM 12b-25

                           NOTIFICATION OF LATE FILING

                                                      SEC File Number: 000-27427
                                                         CUSIP Number: 021489109

(Check One): |_| Form 10-K |_| Form 20-F |_| Form 11-K |X| Form 10-Q

             |_| Form 10-D |_| Form N-SAR |_| Form N-CSR

      For Period Ended December 31, 2005
                       --------------------
      |_|   Transition Report on Form 10-K
      |_|   Transition Report on Form 20-F
      |_|   Transition Report on Form 11-K
      |_|   Transition Report on Form 10-Q
      |_|   Transition Report on Form N-SAR
      |_|   Transition Report on Form N-CSR
      For the Transition Period Ended:_____

Nothing  in this  form  shall be  construed  to imply  that the  Commission  has
verified any information contained herein.

If the notification  relates to a portion of the filing checked above,  identify
the Item(s) to which the notification relates:

                         PART I - REGISTRANT INFORMATION

AltiGen Communications, Inc.
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Full name of registrant

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Former name if applicable

4555 Cushing Parkway
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Address of principal executive office (Street and number)

Fremont, California 94538
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City, state and zip code

                        PART II - RULES 12b-25(b) and (c)

If the subject report could not be filed without  unreasonable effort or expense
and the registrant seeks relief pursuant to Rule 12b-25(b), the following should
be completed.  (Check box if appropriate.)

      (a)   |_| The reasons  described in reasonable  detail in Part III of this
            form could not be eliminated without unreasonable effort or expense;

      (b)   |X| The subject annual report, semi-annual report, transition report
            on Form 10-K,  Form 20-F,  Form 11-K,  Form N-SAR or Form N-CSR,  or
            portion thereof,  will be filed on or before the fifteenth  calendar
            day following  the  prescribed  due date;  or the subject  quarterly
            report or  transition  report on Form 10-Q or  subject  distribution
            report on Form 10-D, or portion thereof,  will be filed on or before
            the fifth calendar day following the prescribed due date; and

      (c)   |_| The  accountant's  statement or other  exhibit  required by Rule
            12b-25(c) has been attached if applicable.




                              PART III - NARRATIVE

State below in reasonable  detail the reasons why Forms 10-K,  20-F, 11-K, 10-Q,
10-D,  N-SAR,  N-CSR or the transition  report or portion thereof,  could not be
filed within the prescribed time period.

The Registrant and its  independent  registered  public  accounting firm require
more time to complete their implementation and review of the financial reporting
requirements of Financial  Accounting  Standard 123R  (FAS123R),  which requires
companies  to  estimate  the cost of all forms of stock based  compensation  and
record the  estimated  compensation  and provide  explanatory  footnotes  in the
financial  statements of the Registrant.  Due to this factor,  the Registrant is
unable,  without  unreasonable  effort  or  expense,  to  complete  and file its
Quarterly  Report on Form 10-Q for the quarter ended  December 31, 2005,  within
the prescribed filing date of February 14, 2006. The Registrant  expects to file
the Form 10-Q within five days after the filing deadline.

                           PART IV - OTHER INFORMATION

(1)   Name  and  telephone  number  of  person  to  contact  in  regard  to this
      notification:

        Philip M. McDermott              (510)                   252-9712
      -----------------------         ----------             -----------------
              (Name)                  (Area Code)            (Telephone Number)

(2)   Have all other periodic  reports required under Section 13 or 15(d) of the
      Securities  Exchange Act of 1934 or Section 30 of the  Investment  Company
      Act of 1940 during the preceding 12 months or for such shorter period that
      the  registrant  was required to file such  report(s)  been filed?  If the
      answer is no, identify report(s). |X| Yes |_| No

(3)   Is it  anticipated  that any  significant  change in results of operations
      from the  corresponding  period for the last fiscal year will be reflected
      by the earnings statements to be included in the subject report or portion
      thereof? |_| Yes |X| No

If so, attach an explanation of the  anticipated  change,  both  narratively and
quantitatively, and, if appropriate, state the reasons why a reasonable estimate
of the results cannot be made.

The  Registrant  anticipates  reporting  loss from  operations of  approximately
$218,000 on  revenues  of  approximately  $4.4  million  for the  quarter  ended
December 31, 2005 as compared to income from  operations of $342,000 on revenues
of $4.3  million  for the  corresponding  prior  year  period.  A more  detailed
discussion of results of operations will be included in Management's  Discussion
and Analysis of Financial  Condition  and Results of Operations in the Form 10-Q
to be filed.

                          AltiGen Communications, Inc.
                  --------------------------------------------
                  (Name of Registrant as Specified in Charter)

has  caused  this  notification  to be signed on its  behalf by the  undersigned
thereunto duly authorized.

Date: February 14, 2006         By:    /s/ Philip M. McDermott
      -----------------         ------------------------------------------------
                                Name:  Philip M. McDermott
                                Title: Senior Vice President and Chief Financial
                                       Officer

INSTRUCTION: The form may be signed by an executive officer of the registrant or
by any other duly  authorized  representative.  The name and title of the person
signing  the form  shall  be typed or  printed  beneath  the  signature.  If the
statement is signed on behalf of the registrant by an authorized  representative
(other than an executive officer), evidence of the representative's authority to
sign on behalf of the registrant shall be filed with the form.

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                                    ATTENTION

Intentional  misstatements  or omissions  of fact  constitute  Federal  Criminal
Violations (See 18 U.S.C. 1001).


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