<PAGE>

                                  LICENSE AGREEMENT

     THIS LICENSE AGREEMENT ("License") is made as of this 21st day of April,
2000 between TH TOWER LEASING LLC, a Delaware limited liability company
("Licensor"), and UNIVERSAL ACCESS, INC., a Delaware corporation ("Licensee");

                                     WITNESSETH:

     WHEREAS, Licensor and Licensee have entered into a Lease dated as of March
10, 2000 (the "Lease") pursuant to which Licensee is leasing from Licensor
certain space in the Sears Tower located at 233 South Wacker Drive, Chicago,
Illinois; capitalized terms used herein shall have the meanings ascribed to such
terms in the Lease; and

     WHEREAS, Licensee desires to license from Licensor the use of certain areas
in the risers and other common areas of the Building upon the terms and
conditions set forth below;

     NOW, THEREFORE, in consideration of the foregoing and for other good and
valuable consideration, the receipt of which is hereby acknowledged, Licensor
and Licensee hereby agree as follows:

     1.   DEMISE/USE.  Licensor licenses to Licensee, and Licensee licenses from
Licensor, certain space constituting a path for interconnecting Licensee's data,
telephone and alarm systems located in the Sixth Floor Premises and in the Third
Floor Premises (the "Licensed Areas").  Licensee shall be permitted to use the
Licensed Areas (after approval of all locations, installation methods and
materials by Licensor) for installation, use and maintenance of (a) one (1)
metallic conduit, the outside diameter of which shall not exceed two inches
(2"), (b) one (1) metallic conduit, the outside diameter of which shall not
exceed three-quarter inches (0.75") and for no other purpose whatsoever.  It is
expressly understood that the interconnection permitted by this License shall be
used only for the interconnection of Licensee's internal systems and not for any
resale of communication service or to circumvent the obligation of all service
providers in the Building to pay Rent for access to the Building.  Except as
expressly provided for herein or as otherwise provided in the Lease, Licensee
shall have no other license or right to use any other portion of the Building
(including, without limitation, the following areas in and about the Building
and Licensed Areas: janitor closets, stairways and stairwells, fan, mechanical,
electrical, telephone and similar rooms; roofs; antenna supports; elevator, pipe
and other vertical shafts, flues and ducts; all areas above any ceiling and
below any floor covering; all other structural or mechanical elements serving
other areas of the Building; and all subterranean, mineral, air, light and view
rights) during the Term without prior written consent of Licensor.

     Licensee shall comply with the requirements of all governmental agencies
concerning the use of the Licensed Areas for the foregoing uses and shall not
directly make any use of the Licensed Areas which may be dangerous to persons or
property, which may jeopardize or increase the cost of any insurance coverage or
require additional insurance coverage.  Upon the execution hereof, Licensee
shall provide Licensor with evidence that Licensee has received all licenses,
approvals and permits required under applicable law, if any, for the foregoing
use (including, without limitation, those from the Federal Communications
Commission ("FCC")) and shall keep all of the foregoing in full force and effect
during the entire Term of this License.

<PAGE>

     2.   TERM.  The term (the "Term") of this License shall commence on April
21, 2000 (the "Commencement Date") and shall terminate (unless sooner terminated
as herein provided) on the earlier to occur of (x) December 31, 2000 and (y) the
date this License Agreement is superseded by a new License Agreement agreed to
by Licensor and Licensee.

     3.   LICENSE FEE.  Licensee shall pay Licensor a fee (the "License Fee") at
the rate of $475.00 per month for use of the Licensed Areas.  Licensee shall pay
said Licensee Fee to Licensor or Licensor's agent at Sears Tower, 233 South
Wacker Drive, Chicago, Illinois on or before the first (1st) day of each month.
Such License Fee shall be deemed part of the Rent due and payable under the
Lease.

     4.   EXPENSES.  Licensee agrees to pay all costs associated with the
installation and maintenance of the conduit licensed in Section 1.

     5.   CONDITION OF LICENSED AREAS.  Licensee shall take possession of the
Licensed Areas in "as-is" condition.  Licensee, at its cost and expense, will
make all repairs and replacements to or upon the Licensed Areas necessitated by
the fault or neglect of Licensee, Licensee's employees and invitees, and will
keep the Licensed Areas in clean condition.  At the end of the Term or earlier
termination of this License, Licensee, except for normal wear and tear and
casualty, shall surrender the Licensed Areas to Licensor in substantially the
same condition as when tendered to Licensee and in "broom clean" condition.
Licensee shall not make any additions or alterations to the Licensed Areas.

     6.   ACCESS TO LICENSED AREAS.  Licensor may show the Licensed Areas to
prospective licensees, tenants of the Building or to any other third parties.

     7.   INCORPORATION OF LEASE PROVISIONS.  Sections 7(b), 9, 10, 12, 13, 17
(except that all references to Rent in such Section shall refer to the License
Fee when incorporated herein), 18, 19, 21, 22, 23, 27 (and Paragraph 8 of the
Schedule) and 28 of the Lease shall be applicable to this License as if set
forth herein in their entirety, except that all references to (x) Tenant in the
Lease shall mean Licensee when incorporated herein, (y) Landlord in the Lease
shall mean Licensor when incorporated herein, and (z) Premises in the Lease
shall mean Licensed Areas when incorporated herein.  To the extent of any
inconsistency between the terms of the Lease and the terms of this License, the
terms of this License shall control.

     8.   DEFAULT/RIGHT TO REENTER.  Licensor may terminate this License or
pursue any other remedy available to it at law or in equity, if:

     (a)  Licensee fails to make any payment due hereunder and such failure
          shall continue for five (5) days after written notice to Licensee; or

     (b)  a default is made in the performance by Licensee of any covenant
          contained herein which involves a hazardous condition and is not cured
          promptly by Licensee upon written notice to Licensee; or

     (c)  Licensee fails to observe or perform any other covenant or agreement
          to be performed by Licensee herein and such default shall continue for
          twenty (20) days after written notice to Licensee; or


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<PAGE>

     (d)  a Default occurs under the Lease.

     9.   NO ASSIGNMENT OR SUBLETTING.  Licensee shall not (i) assign or
otherwise transfer any interest in this License other than to a Permitted
Assignee, (ii) sublet the Licensed Areas or any part thereof, or (iii) permit
the use of the Licensed Areas by any parties other than Licensee or a Permitted
Assignee or their respective employees.

     10.  CONDEMNATION/DAMAGE.  In the event of damage, destruction or eminent
domain takings which render the Licensed Areas or the Building no longer useful
for the purpose intended, either party may terminate this License by giving
written notice to the other party.

     11.  SURRENDER OF POSSESSION.  Upon the expiration of the Term or upon the
termination of Licensee's License, whether by lapse of time or at the option of
Licensor as herein provided, (A) Licensee shall (i) at once vacate the Licensed
Areas, (ii) promptly dismantle and remove Licensee's cables and any other
equipment from any other portions of the Building (other than those portions of
the Building subject to the Lease), provided, however, that to the extent
Licensee's cables cannot be removed or dismantled in a manner which is
consistent with sound engineering practice and which will not disturb or
otherwise affect the structural integrity of any portion of the Building, then
the same shall remain at its location and title thereto shall thereupon
automatically pass to Licensor without any cost either by set-off, credit,
allowance or otherwise, and (iii) subject to the foregoing, repair, at its
expense, any damage caused to the Building, by the existence of such equipment
and/or by such dismantling and removal; and (B) Licensee shall immediately
remove all of its property from the Building (other than those portions of the
Building subject to the Lease) and if such portions of the Building, if any, are
not immediately vacated, Licensor may forthwith remove all persons and effects
therefrom and from the balance of the Building (other than those portions of the
Building subject to the Lease) using such force as may be necessary, without
being deemed guilty of any manner of trespass, eviction or forcible entry or
detainer and without thereby relinquishing any right given to Licensor hereunder
or by operation of law.  If Licensee shall fail or refuse to remove (to the
extent permitted herein) any of the property described herein from any other
portions of the Building (other than those portions of the Building subject to
the Lease), Licensee shall be conclusively presumed to have abandoned same, and
title thereto shall thereupon pass to Licensor without any cost either by
set-off, credit, allowance or otherwise, and Licensor may, at its option, accept
the title to such property or at Licensee's expense may (i) remove the same or
any part in any manner that Licensor shall choose, and (ii) store, destroy or
otherwise dispose of the same without incurring liability to Licensee or any
other person.

     12.  OTHER COMMUNICATIONS FUNCTIONS.  It is hereby acknowledged by Licensee
that Licensor conducts communications activities in, on and about the Building
and has granted to certain other parties the right, during the Term, to engage
in communication activities in, on and about the Building.  Without limitation
of the foregoing, during the Term, Licensor may continue to (A) conduct
communications activities in, on and about the Building, (B) grant to other
parties the right to engage in other communication activities in, on and about
the Building, (C) erect, use and maintain, or to grant other licensees the right
to erect, use and maintain, pipes, ducts, wiring, cables and conduits and
appurtenances thereto, in and about the Building (including, without limitation,
through the areas containing the Licensed Areas), and (D) to attach cables,
ducts antenna masts and broadcast or other communication antennas, to portions
of the Building (or any roof thereof).  Construction resulting from any grant
may from time to time result in the


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<PAGE>

interruption of Licensee's operations in and from the Building for reasonable
periods, it being understood that any such interruption shall never be deemed to
constitute an eviction, constructive or partial eviction or disturbance of the
Licensee's Licensed Areas of the Building or relieve the Licensee from
performing any of its obligations under this License.  Licensee shall conduct
its communications activities in and from the Building as permitted herein
during the Term of this License in a manner which will avoid objectionable
interference (a) with any other licensee's transmission or reception of signals
in, on, about or from the Building and (b) with Licensor's communications
systems within the Building, as such systems may now or hereafter exist.  Upon
determination by Licensor that Licensee's activities are causing such
objectionable interference, Licensee will immediately take such action as may be
required to eliminate such objectionable interference.  Without limitation of
the foregoing, Licensee shall execute and deliver to Licensor such addenda to
this License as Licensor, in the exercise of its discretion, may request from
time to time in order to further evidence and clarify Licensee's covenants and
agreements contained herein to conduct its communications activities in and from
the Building as permitted herein in a manner which will avoid objectionable
interference.

     13.  NO REAL ESTATE BROKER.  Licensee represents that it has not dealt with
any broker in connection with this License, and that insofar as Licensee knows,
no broker negotiated this License or is entitled to any commission in connection
herewith.  Licensee agrees to indemnify, defend and hold Licensor, its agents
and employees, harmless from and against any claims made by any broker for a
commission or fee in connection with this License, provided Licensor has not in
fact retained such broker.

     14.  SUBSTITUTION OF OTHER LICENSED AREAS.  At any time during the Term of
this License, Licensor, upon thirty (30) days prior notice, may substitute for
the Licensed Areas other Licensed Areas in the Building (the "New Licensed
Areas"), provided such New Licensed Areas shall be usable by Licensee for
Licensee's permitted purpose and such New Licensed Areas are substantially
similar to the Licensed Areas.

     15.  MISCELLANEOUS.  The preambles to this License are hereby incorporated
and made a part of this License.

     16.  ENTIRE AGREEMENT/BINDING EFFECT.  This License covers in full every
obligation between the parties hereto concerning the Licensed Areas, and the
provisions of this License shall be binding upon and shall inure to the benefit
of the parties hereto and their respective heirs, executor, administrators,
successors and assigns, as the case may be.


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<PAGE>

     IN WITNESS WHEREOF, Licensor and Licensee have executed this License as of
the day and year first above written.

                              LICENSEE:

                              UNIVERSAL ACCESS, INC., a Delaware corporation


                              By:  /s/ Robert Brown
                                 -----------------------------------------------
                              Printed Name:
                                           -------------------------------------
                              Its:
                                  ----------------------------------------------


                              LICENSOR:

                              TH TOWER LEASING, LLC, a Delaware
                              limited liability company


                              By:  /s/ Stephen Budorick
                                 -----------------------------------------------
                              Printed Name: STEPHEN BUDORICK
                                           -------------------------------------
                              Its:   VICE PRESIDENT
                                  ----------------------------------------------


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