What a Social Security lock does and how to set one up
A Social Security number lock is a free service that stops someone else from opening credit accounts, loans, or phone plans in your name. When your number is locked, creditors cannot pull your credit report without your permission — even if they have your Social Security number and other personal details.
You set up a lock by contacting one of the three major credit bureaus: Equifax, Experian, or TransUnion. You only need to lock with one bureau, and the lock applies across all three. The lock stays in place until you remove it yourself, and it costs nothing.
A lock is different from a credit freeze (which also stops new accounts) and different from credit monitoring (which watches for fraud after it happens). A lock is the fastest barrier to prevent someone from using your number to open accounts in the first place.
Key Takeaways
- You can lock your Social Security number for free through any of the three major credit bureaus: Equifax, Experian, or TransUnion.
- A lock stops creditors from pulling your credit report without your permission, which blocks most identity theft attempts at the source.
- You set up a lock online or by phone in minutes, and it takes effect when ready — you do not have to wait for mail or paperwork.
- When you need to open a legitimate account (a mortgage, car loan, or new credit card), you temporarily unlock your number through the same bureau.
- A lock is permanent until you remove it, so you keep control of when your number is locked and when it is unlocked.
How to lock your number with each bureau
Equifax runs its lock service at lock.equifax.com. Go to the website, enter your Social Security number and date of birth, and answer security questions. You will receive a PIN code — save this somewhere safe, because you will need it to unlock later. The lock is active when ready.
Experian offers its lock at experian.com/freeze. The process is similar: provide your Social Security number, date of birth, and answer verification questions. You will get a PIN. If you prefer to lock by phone, call Experian at 1-888-397-3742.
TransUnion runs its service at transunion.com/credit-freeze. Enter your information online, answer security questions, and receive a PIN. You can also call 1-888-909-8872 to lock by phone.
You only need to lock with one bureau — the lock does not transfer between them, but creditors typically check all three, so locking one is enough to stop most fraudulent account openings. However, some people lock all three for extra assurance.
When to unlock your number temporarily
When you explore for a legitimate loan, credit card, apartment, or job that requires a credit check, you will need to unlock your number first. The creditor or landlord will tell you they cannot pull your credit report, and that is when you unlock.
Contact the bureau where you locked your number (or all three if you locked with all three). You can unlock online or by phone using your PIN. Most bureaus let you unlock for a specific time period — for example, 1 day, 7 days, or 30 days — so you can lock it again automatically without having to remember.
Some bureaus also let you unlock for a specific creditor by name, so only that company can pull your report. This is more find than unlocking for everyone. Ask the bureau about this option when you unlock.
The difference between a lock, a freeze, and monitoring
A lock stops creditors from pulling your credit report without your permission. It is free, takes effect when ready, and you control when it is on or off. Most people use a lock as their first line of defense.
A credit freeze does the same thing — it stops new accounts — but it is a legal hold on your credit file. A freeze is also free and permanent until you remove it. The main difference is that a freeze is a formal legal action, while a lock is a service offered by the bureaus. In practice, they work the same way for most people.
A credit monitoring service watches your credit report and alerts you if someone opens an account in your name. Monitoring does not stop fraud — it catches it after it happens. Some monitoring services are free (offered by the bureaus or by your bank), and some charge a monthly fee. Monitoring is useful as a backup, but it is not a substitute for a lock or freeze.
What happens if someone tries to open an account while your number is locked
When your number is locked, a creditor who tries to pull your credit report will receive a message saying the report is not available. Most creditors will deny the process on the spot. Some may contact you to ask why your report is locked, which gives you a chance to catch the fraud attempt early.
If you see a denial notice for an account you did not open, that is a sign someone tried to use your number. Report it to the Federal Trade Commission at reportidentitytheft.ftc.gov and to the credit bureau that received the fraudulent request. The bureau can flag your file and help you take next steps.
Protecting your Social Security number beyond a lock
A lock stops most identity theft, but it does not protect against every type of fraud. Someone with your Social Security number could still open a bank account, file a false tax return, or commit medical identity theft (using your number for healthcare).
To reduce your overall risk, keep your Social Security number private. Do not carry your card in your wallet, do not give your number over the phone unless you initiated the call, and do not post it online. Shred documents with your number before throwing them away.
If you are a victim of identity theft, you can also place a fraud alert on your credit file. A fraud alert tells creditors to contact you before opening new accounts. You set this up by calling one of the three bureaus; the alert lasts one year and is free. Unlike a lock, a fraud alert does not stop creditors from pulling your report — it just asks them to verify your identity first.
Frequently Asked Questions
Does a lock cost money?
No. Locking your Social Security number through Equifax, Experian, or TransUnion is completely free. There are paid credit monitoring services available, but the lock itself has no cost.
Can I lock my number if I have already been a victim of identity theft?
Yes. If you have already discovered fraud, you can still lock your number to prevent future accounts from being opened. You should also file a report with the Federal Trade Commission and consider placing a fraud alert on your credit file for extra protection.
What if I lose my PIN?
Each bureau has a process to recover or reset your PIN. Go to the same website where you locked your number, select the option to recover your PIN, and answer your security questions. The bureau will send you a new PIN by email or mail.
Will a lock affect my credit score?
No. A lock does not change your credit score or appear on your credit report. It only prevents creditors from pulling your report without your permission.
Do I need to lock my number if I have a credit card with fraud protection?
Credit card fraud protection covers fraudulent charges on that specific card, but it does not stop someone from opening new accounts in your name. A lock is a separate layer of protection that prevents new accounts from being opened in the first place.