Each carrier takes a different stance on what is materially adverse, who can get out (Cingular for instance has eliminated language in some contracts that claims that text messages for instance are an "optional service"). You usually (except for Verizon which does offer 60 day period to call and claim materially adverse) only have a short time to claim a change as materially adverse, sometimes less than 14 days. Listen to UCAN attorney Art Neill's tips to cancelling your contract here [1].
Cingular [2]
Sprint/Nextel [3]
T-Mobile [4]
Verizon [5]
CTIA-International Association for Wireless Telecommunications [6]
CINGULAR
Changes to the terms and conditions: These terms and conditions may be changed from time-to-time. Cingular will post the most current version of these terms and conditions on the MEdia Net web site (www.cingular.com/medianet [7]) or other appropriate location. Please check these regularly to inform yourself about changes to the terms and conditions, policies, news, etc.
SPRINT/NEXTEL
When You Don't Have To Pay An Early Termination Fee
You aren't responsible for paying an Early Termination Fee when terminating Services: (a) provided on a month-to-month basis; (b) consistent with our published trial period return policy; or (c) in response to a materially adverse change we make to the Agreement as described directly below.
Our Right To Change The Agreement & Your Related Rights
We may change any part of the Agreement at any time including, but not limited to, rates, charges, how we calculate charges, or your terms of Service. We will provide you notice of changes that may impact you in a manner consistent with this Agreement (see "Providing Notice Under This Agreement" paragraph). Except as provided below, if a change we make to the Agreement is material and has a material adverse affect on you, you may terminate each line of Service materially affected without incurring an Early Termination Fee only if you: (a) call us within 30 days after the effective date of the change; and (b) specifically advise us that you wish to cancel Services because of a material change to the Agreement that we have made. If you do not cancel Service within 30 days of the change, an Early Termination Fee will apply if you terminate Services before the end of any applicable Term Commitment.
The following, without limitation, will generally not be considered changes to the Agreement as contemplated in this provision and will not result in the waiver of applicable Early Termination Fees: (a) changes to our Policies; (b) changes to rates or charges that are not a core part of the rate plan package for which you contracted - for example, incidental, occasional or casual use charges and other options that do not require a Term Commitment; (b) changes to Taxes & Government Fees; or (c) changes to Surcharges, including assessing new Surcharges.
Our Right To Suspend Or Terminate Services
We can, without notice, suspend or terminate any Service at any time for any reason, including, but not limited to: (a) late payment; (b) exceeding an Account Spending Limit ("ASL"); (c) harassing/threatening our employees or agents; (d) providing false information; (e) interfering with our operations; (f) using/suspicion of using Services in any manner restricted by or inconsistent with the Agreement; (g) breaching the Agreement, including our Policies; (h) providing false, inaccurate, dated or unverifiable identification or credit information, or becoming insolvent or bankrupt; (i) modifying a Device from its manufacturer specifications; or (j) if we believe the action protects our interests, any customer's interests or our network.
T-MOBILE
Changes to the Agreement or Charges. EXCEPT TO THE EXTENT PROHIBITED BY LAW, IF WE: (A) INCREASE THE CHARGES INCLUDED IN YOUR MONTHLY RECURRING ACCESS RATE PLAN, OR (B) MODIFY A MATERIAL TERM OF OUR AGREEMENT WITH YOU AND THE MODIFICATION WOULD BE MATERIALLY ADVERSE TO YOU, WE WILL NOTIFY YOU OF THE INCREASE OR MODIFICATION AND YOU CAN CANCEL THAT SERVICE WITHOUT PAYING A CANCELLATION FEE (WHICH IS YOUR ONLY REMEDY) BY FOLLOWING THE CANCELLATION INSTRUCTIONS IN THE NOTICE. IF YOU DO NOT CANCEL YOUR SERVICE BY FOLLOWING THOSE INSTRUCTIONS, OR YOU OTHERWISE ACCEPT THE CHANGE, THEN YOU AGREE TO THE INCREASE OR MODIFICATION, EVEN IF YOU PAID FOR SERVICE IN ADVANCE. IF THE NOTICE DOES NOT SAY HOW LONG YOU HAVE TO CANCEL, THEN IT IS WITHIN 14 DAYS AFTER THE DATE OF THE NOTICE, UNLESS A LONGER PERIOD IS REQUIRED BY LAW. EXCEPT TO THE EXTENT PROHIBITED BY LAW, CHARGES FOR PRODUCTS, SERVICES, OPTIONAL SERVICES, OR ANY OTHER CHARGES THAT ARE NOT INCLUDED IN YOUR MONTHLY RECURRING ACCESS RATE PLAN (SUCH AS DIRECTORY ASSISTANCE, ROAMING, DOWNLOADS, AND THIRD-PARTY CONTENT) ARE SUBJECT TO CHANGE AT ANY TIME WITHOUT NOTICE, AND IF YOU CONTINUE TO USE THOSE SERVICES, OR YOU OTHERWISE AGREE TO THE CHANGES, THEN YOU AGREE TO THE NEW CHARGES. VISIT OUR WEB SITE, RETAIL LOCATIONS, OR CALL CUSTOMER CARE FOR CURRENT CHARGES.
VERIZON
Our Rights To Make Changes
Your service is
subject to our business policies, practices, and procedures, which we
can change without notice. UNLESS OTHERWISE PROHIBITED BY LAW, WE CAN
ALSO CHANGE PRICES AND ANY OTHER CONDITIONS IN THIS AGREEMENT AT ANY
TIME BY SENDING YOU WRITTEN NOTICE PRIOR TO THE BILLING PERIOD IN WHICH
THE CHANGES WOULD GO INTO EFFECT. IF YOU CHOOSE TO USE YOUR SERVICE
AFTER THAT POINT, YOU'RE ACCEPTING THE CHANGES. IF THE CHANGES HAVE A
MATERIAL ADVERSE EFFECT ON YOU, HOWEVER, YOU CAN END THE AFFECTED
SERVICE, WITHOUT ANY EARLY TERMINATION FEE, JUST BY CALLING US WITHIN
60 DAYS AFTER WE SEND NOTICE OF THE CHANGE.
CTIA CONSUMER CODE
Provide Customers the Right to Terminate Service for Changes to Contract Terms
Carriers will not modify the material terms of their subscribers' contracts in a manner that is materially adverse to subscribers without providing a reasonable advance notice of a proposed modification and allowing subscribers a time period of not less than 14 days to cancel their contracts with no early termination fee.