EXHIBIT 99.3
 
                        NEXTLINK COMMUNICATIONS, L.L.C.
                            NEXTLINK CAPITAL, INC.
 
                               OFFER TO EXCHANGE
                      $350,000,000 IN PRINCIPAL AMOUNT OF
                    12 1/2% SENIOR NOTES DUE APRIL 15, 2006
                      IN RELIANCE UPON AN EXEMPTION FROM
           REGISTRATION UNDER THE SECURITIES ACT OF 1933, AS AMENDED
                                      FOR
                      $350,000,000 IN PRINCIPAL AMOUNT OF
                    12 1/2% SENIOR NOTES DUE APRIL 15, 2006
 
To Our Clients:
 
  Enclosed for your consideration is a Prospectus dated      , 1996 (as the
same may be amended or supplemented from time to time, the "Prospectus") and a
form of Letter of Transmittal (the "Letter of Transmittal") relating to the
offer (the "Exchange Offer") by NEXTLINK Communications, L.L.C. (the
"Company") and NEXTLINK Capital, Inc. (together with the Company, the
"Issuers") to exchange up to $350,000,000 in principal amount of their 12 1/2%
Senior Notes due April 15, 2006 in reliance upon an exemption from
registration under the Securities Act of 1933, as amended (the "Senior
Notes"), for $350,000,000 in principal amount of their 12 1/2% Senior Notes
due April 15, 2006 (the "Exchange Notes").
 
  The material is being forwarded to you as the beneficial owner of Senior
Notes carried by us for your account or benefit but not registered in your
name. A tender of any Senior Notes may be made only by us as the registered
holder and pursuant to your instructions. Therefore, the Issuers urge
beneficial owners of Senior Notes registered in the name of a broker, dealer,
commercial bank, trust company or other nominee to contact such registered
holder promptly if they wish to tender Senior Notes in the Exchange Offer.
 
  Accordingly, we request instructions as to whether you wish us to tender any
or all Senior Notes, pursuant to the terms and conditions set forth in the
Prospectus and Letter of Transmittal. We urge you to read carefully the
Prospectus and Letter of Transmittal before instructing us to tender your
Senior Notes.
 
  YOUR INSTRUCTIONS TO US SHOULD BE FORWARDED AS PROMPTLY AS POSSIBLE IN ORDER
TO PERMIT US TO TENDER SENIOR NOTES ON YOUR BEHALF IN ACCORDANCE WITH THE
PROVISIONS OF THE EXCHANGE OFFER. The Exchange Offer will expire at 5:00 p.m.,
Eastern Standard Time, on      , 1996, unless extended (the "Expiration
Date"). Senior Notes tendered pursuant to the Exchange Offer may be withdrawn,
subject to the procedures described in the Prospectus, at any time prior to
the Expiration Date.
 
  If you wish to have us tender any or all of your Senior Notes held by us for
your account or benefit, please so instruct us by completing, executing and
returning to us the instruction form that appears below. The accompanying
Letter of Transmittal is furnished to you for informational purposes only and
may not be used by you to tender Senior Notes held by us and registered in our
name for your account or benefit.

 
                                 INSTRUCTIONS
 
  The undersigned acknowledge(s) receipt of your letter and the enclosed
material referred to therein relating to the Exchange Offer of NEXTLINK
Communications, L.L.C. and NEXTLINK Capital, Inc.
 
  THIS WILL INSTRUCT YOU TO TENDER THE PRINCIPAL AMOUNT OF SENIOR NOTES
INDICATED BELOW HELD BY YOU FOR THE ACCOUNT OR BENEFIT OF THE UNDERSIGNED AND
TO DELIVER THE UNDERSIGNED'S CONSENT WITH RESPECT TO SUCH SENIOR NOTES,
PURSUANT TO THE TERMS OF AND CONDITIONS SET FORTH IN THE PROSPECTUS AND THE
LETTER OF TRANSMITTAL.
 
Box 1 [_]Please tender my Senior Notes held by you for my account or benefit
         and deliver my Consent with respect to such Senior Notes. I have
         identified on a signed schedule attached hereto the principal amount
         of Senior Notes to be tendered, in integral multiples of $1,000, if I
         wish to tender less than all of my Senior Notes.
 
Box 2 [_]Please do not tender any Senior Notes held by you for my account or
         benefit and do not deliver my Consent.
 
Date:       , 1996
 
                                          _____________________________________
                                          _____________________________________
                                                      Signature(s)
                                          _____________________________________
                                          _____________________________________
                                                Please print name(s) here
 
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Unless a specific contrary instruction is given in a signed Schedule attached
hereto, your signature(s) hereon shall constitute an instruction to us to
tender all your Senior Notes and to deliver your Consent with respect thereto.