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

                                 FORM 12b-25

                         NOTIFICATION OF LATE FILING

                                                Commission File Number  0-19494
                                                                       ---------
(Check One):

[X] Form 10-K and Form 10-KSB               [ ] Form 11-K

[ ] Form 20-F            [ ] Form 10-Q and Form 10-QSB            [ ] Form N-SAR

For Period Ended:     December 31, 1999
                  --------------------------------------------------------------

[ ] Transition Report on Form 10-K and Form 10-KSB

[ ] Transition Report on Form 20-F

[ ] Transition Report on Form 11-K

[ ] Transition Report on Form 10-Q and Form 10-QSB

[ ] Transition Report on Form N-SAR

For the Transition Period Ended:
                                 -----------------------------------------------

    Read Attached Instruction Sheet Before Preparing Form. Please Print or Type.

    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


    Full name of registrant   PAGING NETWORK, INC.
                            --------------------------------------------------
    Former name if applicable
                              ------------------------------------------------

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

    Address of principal executive office (Street and number)
                                                              ----------------
                    14911 QUORUM DRIVE
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    City, state and zip code     DALLAS, TEXAS 75240
                             -------------------------------------------------

                                    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.)

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

[X] (b)  The subject annual report, semi-annual report, transition report on
         Form 10-K, 10-KSB, Form 20-F, 11-K, Form N-SAR, or portion thereof
         will be filed on or before the 15th calendar day following the
         prescribed due date; or the subject quarterly report or transition
         report on Form 10-Q, 10-QSB, 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, 10-KSB, 11-K,
20-F, 10-Q, 10-QSB, N-SAR or the transition report or portion thereof, could not
be filed within the prescribed time period. (Attach extra sheets if needed.)

               (See Attachment)

                                    12b25-1
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                                    PART IV
                               OTHER INFORMATION

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

   JULIAN B. CASTELLI                              (972) 801-8145
- --------------------------------------------------------------------------------
     (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 reports) been filed?  If 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?

                                                             [X] Yes      [ ] 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. (See Attachment)

                              PAGING NETWORK, 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:   MARCH 30, 2000         By:   /s/ JULIAN B. CASTELLI
      ------------------------     ---------------------------------------------
                                    Julian B. Castelli, Senior Vice-President &
                                    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.

                                   ATTENTION

    Intentional misstatements or omissions of fact constitute federal criminal
violations (see 18 U.S.C. 1001).



                             GENERAL INSTRUCTIONS

1.  This form is required by Rule 12b-25 of the General Rules and Regulations
    under the Securities Exchange Act of 1934.

2.  One signed original and four conformed copies of this form and amendments
    thereto must be completed and filed with the Securities and Exchange
    Commission, Washington, D.C. 20549, in accordance with Rule 0-3 of the
    General Rules and Regulations under the Act.  The information contained in
    or filed with the form will be made a matter of public record in the
    Commission files.

3.  A manually signed copy of the form and amendments thereto shall be filed
    with each national securities exchange on which any class of securities of
    the registrant is registered.

4.  Amendments to the notifications must also be filed on form 12b-25 but need
    not restate information that has been correctly furnished.  The form shall
    be clearly identified as an amended notification.

5.  Electronic Filers. This form shall not be used by electronic filers unable
    to timely file a report solely due to electronic difficulties. Filers unable
    to submit a report within the time period prescribed due to difficulties in
    electronic filing should comply with either Rule 201 or Rule 202 of
    Regulation S-T or apply for an adjustment in filing date pursuant to
    Rule 13(b) of Regulation S-T.

                                    12b25-2
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                              PAGING NETWORK INC.
                                  FORM 12b-25


PART III - NARRATIVE


        On November 8, 1999, Paging Network, Inc. (the "Company") announced a
definitive agreement to merge with Arch Communications Group, Inc. ("Arch").
This transaction requires the Company and Arch to make filings with various
regulatory agencies, including the filing of three registration statements with
the Securities and Exchange Commission. The Company and Arch have made such
filings, and are currently in the process of responding to inquiries regarding
the information contained therein and providing additional information. These
efforts have required and continue to require a significant portion of the
Company's available resources in its accounting and finance organizations, and
as well as significant management attention. Additionally, in connection with
the Company's previously announced restructuring, the Company has converted a
significant portion, but not all, of its customer base to new billing and
customer service software platforms. Such conversions have increased the time
required to close the Company's accounting records for the year ended December
31, 1999. Furthermore, as a result of the restructuring and the announcement of
the proposed merger with Arch, the Company has experienced a significant
increase in its employee turnover, including its accounting, finance, and
information technology organizations resulting in fewer resources to handle the
year-end reporting. For all of these reasons, the Company is unable to timely
complete its Annual Report on Form 10-K for the year ended December 31, 1999,
without unreasonable effort.



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                              PAGING NETWORK, INC.
                                  FORM 12b-25


PART IV (3) - SIGNIFICANT CHANGE IN RESULTS OF OPERATIONS

     The Company expects a significant change in the results of operations for
the year ended December 31, 1999 compared to the year ended December 31, 1998.
The Company expects a decrease in total revenues, the amount of which cannot be
determined at the present time due to the aforementioned reasons addressed in
the Part III of this filing. The Company expects an increase in operating
expenses in excess of $50 million and an increase in net loss in excess of $100
million.