How to Set Up Carrier Port-Out Locks & Number Transfer PINs
Why Port-Out Protection Matters
Your phone number is more than just a way people reach you — it is a key to your digital identity. Banking apps, email accounts, social media platforms, and cryptocurrency exchanges all use your phone number for verification. If someone transfers your number to their device or to another carrier without your authorization, they can intercept those verification codes and compromise your accounts. Port-out protection and number transfer PINs are the most direct defenses against this type of attack. Setting them up takes five minutes and provides ongoing protection against both SIM swap attacks and unauthorized number ports.
Setting Up Port-Out Protection by Carrier
T-Mobile
T-Mobile offers two distinct protections. SIM Protection prevents your number from being moved to a different SIM card on T-Mobile's network. Enable it through the T-Life app: tap your name, then Profile, then Privacy and Notification, then SIM Protection, and toggle it on. Port Out Protection blocks your number from being transferred to a different carrier entirely. This is available for all T-Mobile postpaid, prepaid, and Metro by T-Mobile customers. Add Port Out Protection through the add-ons section of the T-Life app or your online account. Both features are free. When you legitimately want to switch carriers or change devices, you will need to temporarily disable these protections — which requires your account PIN, adding another layer of security.
Verizon
Verizon offers Number Lock through the My Verizon app. When enabled, Number Lock prevents your number from being ported out to another carrier. To enable it: open the My Verizon app, go to Account, then select the line you want to protect, then look for Number Lock under Security or Account settings. You will need to unlock the number temporarily when you legitimately want to port to a new carrier. Verizon also requires a four-digit account PIN for any account changes, including SIM swaps. Set this PIN through the My Verizon app under Security settings. Choose a random four-digit number — do not use your birthday or any easily guessable sequence.
AT&T
AT&T provides extra security through the myAT&T app and website. You can set a passcode on your account that must be provided before any changes are processed, including port-out requests. AT&T also generates a transfer PIN when you are ready to legitimately port your number out — this PIN expires after a set period, reducing the window for unauthorized use. To set up account security: log in to myAT&T, navigate to Profile, then Sign-in info, and set your wireless passcode. AT&T does not currently offer a one-click "port lock" like T-Mobile, but the combination of account passcode and the transfer PIN system provides similar protection.
MVNO and Prepaid Carriers
Prepaid and MVNO carriers vary in their port-out protection offerings. Mint Mobile and US Mobile support account PINs but do not offer dedicated port-out lock features. Visible allows you to set an account PIN. Cricket Wireless, as an AT&T subsidiary, uses AT&T's security infrastructure. When using an MVNO, your account PIN is your primary protection — set it immediately after activation and choose a PIN that is not derived from personal information. Some MVNOs generate a transfer PIN only when you explicitly request it through the app, which naturally limits unauthorized port-out attempts.
Transfer PINs vs. Account PINs
These are different things and it is important to understand the distinction. An account PIN (sometimes called a security PIN or passcode) is a number you set proactively to authenticate yourself when contacting the carrier or making account changes. A transfer PIN is generated by the carrier when you want to port your number to a new carrier — it is part of the port-out process and is typically temporary. Both are important. Your account PIN protects against unauthorized changes to your account. The transfer PIN is required by the receiving carrier during a legitimate port-out. Together, they create a two-layer verification system.
What to Do After Setting Up Protection
After enabling port-out locks and account PINs, take these additional steps. Write down your PINs and store them securely — a password manager is ideal. Set up a carrier account with a strong, unique password separate from your other accounts. Enable notifications for account changes if your carrier offers them. Review your authorized users list — on postpaid accounts, any authorized user can potentially make changes. Remove former family members, ex-partners, or anyone who no longer needs account access. Check your account settings quarterly to ensure protections are still enabled — some carrier system updates have been known to reset security settings.
For the broader context of why these protections matter, see our Complete SIM Swap Protection Guide. For privacy-focused plan options, see our Best Anonymous Prepaid Plans.
Common Mistakes When Setting Up Port-Out Protection
The most common mistake is using a PIN derived from personal information — birthdays, addresses, phone numbers, or Social Security digits. Attackers specifically target these because they are easy to obtain from data breaches and social media. Use a random PIN generated by a password manager. Another common error is setting up protection on the primary line but forgetting secondary lines — if your family plan has four lines, each line needs its own protection. Business accounts are particularly vulnerable because multiple authorized users may have the ability to make changes, and not all of them may follow the same security practices. Audit your authorized users list and remove anyone who no longer needs access.
What Happens When You Legitimately Need to Port Out
When you decide to switch carriers, having port-out protection enabled means you need to take an extra step before the port can process. On T-Mobile, you disable Port Out Protection through the T-Life app using your account PIN, then initiate the port with your new carrier. On Verizon, you unlock your Number Lock through the My Verizon app. This deliberate friction is the entire point — it ensures that only you, with access to your account and knowledge of your PIN, can authorize a number transfer. The extra thirty seconds of effort is trivial compared to the protection it provides. Plan to disable your port protection on the same day you initiate the port with your new carrier to minimize the window of vulnerability.
Frequently Asked Questions
What is a port-out lock?
A port-out lock prevents your phone number from being transferred to another carrier without your explicit authorization. It protects against both SIM swap attacks and unauthorized number porting.
How do I set up port-out protection on T-Mobile?
Open the T-Life app, tap your name, go to Profile, then Privacy and Notification, and enable SIM Protection. For Port Out Protection, add it through the add-ons section of the app. Both features are free.
What is the difference between an account PIN and a transfer PIN?
An account PIN is a number you set proactively to authenticate yourself for account changes. A transfer PIN is generated by the carrier when you want to port your number out and is typically temporary.
Do MVNOs offer port-out protection?
Most MVNOs support account PINs but do not offer dedicated port-out lock features. Your account PIN is the primary protection on MVNO carriers.