You need your account number to switch your T-Mobile phone number to a new carrier or get information about your T-Mobile account. This number is given to you when you buy a SIM card and a plan from T-Mobile. You also need your T-Mobile account number to change sensitive account information, such as your name or date of birth. The account number is a unique identifier that helps your carrier provide you with information about your account.
T-Mobile and other carriers, including Verizon, AT&T, and Sprint, provide their users with an account number. We comparedT-Mobile with VerizonandAT&Tto help you understand which is best for you. This guide helps you find your T-Mobile account number for prepaid and postpaid plans.

How to know your T-Mobile account number
There are multiple ways to find your T-Mobile account number. Let’s go through them one by one.
Check your account number online
You can use your T-Mobile online account to get your account number. Go to the T-Mobileuser login pageand enter your login credentials (your email, phone number, or username, along with your password). When you’re logged in, go to your account page and check the account number displayed in the upper-right corner of your account page.
Find your account number on your paper or digital bill
You’ll find your account number at the top of your monthly paper bill. You can also check the PDF bill to get your account number. It is usually noted in the upper-right corner of the bill. To get the digital bill in PDF format, follow the steps below:
Add 1 to get your account number
Your account number is easy to know and remember if you are a T-Mobile prepaid account holder. Add 1 to the front of your 10-digit phone number. That is your account number. For example, if your phone number is 1234567890, your account number is 11234567890.
Visit your nearest T-Mobile store
When you pass a local T-Mobile store near you, walk in, ask them to help locate your account number, and they will assist you.
The above methods help you find a T-Mobile account number. You should keep it handy, as it is a unique identifier associated with your T-Mobile account that can help you with your account management.
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What is my T-Mobile PIN number?
The PIN number or passcode isn’t the same as if you used to log in to the T-Mobile app or T-Mobile.com account. The PIN or passcode should contain 6 to 15 non-sequential numbers. The PIN/Passcode verifies your account and identity when you contact customer service.
Similar to your T-Mobile account number, your T-Mobile PIN/Passcode is an important identifier. As per theofficial T-Mobile support, there shouldn’t be any of the below:
You can reset your T-Mobile PIN and get a new PIN using the T-Mobile app on your mobile device or via the T-Mobile website. Let’s go through each method one by one.
Using the T-Mobile app
Using a T-Mobile online account
Know these T-Mobile account details to troubleshoot issues easily
If you have issues with T-Mobile services, contact T-Mobile customer service to troubleshoot the problems. You’ll need your T-Mobile account number and your PIN/Passcode handy. If you plan to switch to T-Mobile, check out our list of thebest T-Mobile phonesyou can buy.