How to Complete the T-Mobile Change of Responsibility Form: Eligibility, Balances, Billing

A T-Mobile Change of Responsibility transfers ownership of one or more lines from one person to another without changing the phone number, and it requires both the current account holder and the person taking over to call T-Mobile and authorize the move. The whole process must be finished within 30 days or the request expires and has to be restarted.¹ Consumer transfers happen by phone; business transfers use a form.

Who Qualifies

Both accounts involved must be in good standing. Neither can be past due, delinquent, or in write-off status, so clear any unpaid balance before you start.¹

The line you want to move must have been active on the current account for at least 90 days. Newer lines are not eligible. You can transfer a single line off a multi-line account or hand over the whole account at once.¹

The person taking over must be at least 18, or at least 21 in Puerto Rico. T-Mobile will run a credit check on them, and depending on the result, a deposit may be required. They may also have to pick a new rate plan if the current one is no longer offered or does not fit their account type.¹

What to Have Ready Before Calling

The current account holder needs the account PIN or passcode, the exact phone numbers being transferred, and the receiving party’s full legal name and email address.

The receiving party needs a Social Security number for the credit check, the means to pay a deposit if one is required, and a willingness to accept a different rate plan if the original one is not available.

How the Transfer Works

Consumer and Postpaid Accounts

Both parties call T-Mobile Customer Service at 1-800-937-8997 to authorize the change. Once both authorizations are in, someone has to contact T-Mobile’s activations team within 30 days to finalize the transfer. Miss that window and the original owner starts over.¹

After the original owner completes their portion, the accepting party has a separate 30-day window to finish theirs. That is when the new owner agrees to the service terms, completes the credit check, and confirms they accept any equipment installment balance attached to the line.¹

Business Accounts

Business transfers use paperwork instead of a call. For accounts with 21 lines or fewer, download T-Mobile’s Business Change of Responsibility form, fill it out and sign it, then email it to BusinessCare@T-MobileSupport.com or fax it to 1-877-214-5937. Accounts with 22 or more lines have to go through Business Customer Service directly.¹

Device Payment Balances Move With the Line

If the transferring line has money left on an equipment installment plan, T-Mobile will try to move that balance to the new owner, who has to be able and willing to take it on. If they cannot or will not, the original owner keeps the debt. And if the original owner’s account has no active lines left after the transfer, the full remaining EIP balance hits their final bill.¹

This is where people get caught. A line with $400 left on the phone can turn into a lump-sum charge if the receiving party can’t accept it. Confirm the handoff before you authorize anything.

Promotions End; Some Device Credits Can Survive

Service promotions do not transfer. No exceptions, including for a deceased customer’s account. Promotional rates, free-line deals, and other service discounts end once the transfer goes through.¹

Recurring device credits from a trade-in promotion can follow the line, but only when all three of these are true:

The line has an active, unpaid equipment installment plan.
The EIP and the phone number transfer together to the new owner.
The new owner is on an eligible rate plan.

If any one condition fails, the credits stop. Credits tied to add-a-line or port-in promotions follow the same rule: every original condition of the promotion has to be satisfied on the new owner’s account, or the credits end.¹

Billing After the Handoff

The original account holder owes every charge up to the moment the transfer completes. Any existing balance stays with them and does not follow the line. The new owner picks up all charges from the transfer date forward and gets a new billing cycle and due date.¹

Do These Things Before Authorizing

Back up voicemails. The voicemail box may be deleted during the transfer and saved messages lost.¹
Check what rate plans the new owner can actually get. A grandfathered or retired plan usually cannot be kept, so ask before finalizing.¹
Add up any monthly credits and service discounts on the line so both sides know what will disappear.
Expect a lag. It may take up to a week after the transfer before the new owner can register the line on My T-Mobile or the T-Life app.

When the Account Holder Has Died

A Change of Responsibility can still be processed for a deceased customer, but T-Mobile needs extra documentation: the account holder’s name, mobile number, and account number, plus a death certificate or other legal document confirming the death. Service promotions still do not transfer. Contact T-Mobile Customer Service to start the process and confirm which documents apply to your situation.¹

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T-Mobile. Transfer Account or Line Ownership