Lost Your Phone? Here’s How to Block Your Bank Account Instantly

You lose your phone or ATM card, notice suspicious transactions on your account, or click a fishy link and suspect your account details were compromised.

In moments like these, every second counts. Fraudsters work fast, and so should you. This isn't the time for poor internet connection, bank queues, and customer service delays

Thankfully, you can block your bank account in seconds using USSD codes. No internet, no banking app, no queues or customer service delays. Just your mobile phone and a simple code. Here's how to do it.

READ ALSO: How to Block a Stolen Phone from Accessing Your Bank Account

What’s a USSD Code, and Why Is It a Lifesaver?

USSD stands for Unstructured Supplementary Service Data, but let’s skip the jargon.

In plain English, it’s the short code you dial on your phone (like *737#) to access banking services without the internet.

And guess what? Most banks now let you block your account with a simple USSD code—no need to wait in line at the bank or call customer service while someone drains your money.

How to Block Your Bank Account with USSD

The Basic Format:

Each bank has its code, but generally:

• Dial the bank’s emergency USSD code from any phone, not just the one linked to your account.

• Follow the prompt (some ask for your account number or other ID).

• Confirm the block.

USSD Codes to Block Your Bank Account (All Nigerian Banks Covered)

Here’s a detailed list of all major Nigerian banks and how to block your account quickly using USSD:

1. GTBank

• Code: Dial 73751*10#

• Alternative: Call GTConnect: 08029002900 or 0700482666328

You can dial this from any phone (even if it’s not your registered number)

2. Access Bank

• Code: Dial 901911#

• How it works: You’ll be prompted to enter the phone number linked to your account and select the reason.

• Alternative: Call 07003000000

READ ALSO: OPay USSD Codes To Check Balance, Transfers, Airtime, and More

3. Zenith Bank

• Code: Dial 966911#

• Instructions: Enter your account number, then select the option to block your account.

4. UBA (United Bank for Africa)

• Code: Dial 919911#

• What happens: The code locks your account and prevents further transactions.

• Alternative: Call 01-2808822

5. First Bank

• Code: Dial 894911#

• Instructions: Enter your registered phone number and account details when prompted.

6. Fidelity Bank

• Code: Dial 770911#

• What you need: Your registered phone number. Follow the prompts to lock the account instantly.

7. Union Bank

• Code: Dial 8266#

• Next steps: Select the option to block your account.

8. Sterling Bank

• Code: Dial 822911#

• Details: Follow the instructions to block your account temporarily.

9. Ecobank

• Code: Dial 326911#

• Note: Works even if you’re using a different phone number.

10. FCMB (First City Monument Bank)

• Code: Dial 329911#

• Instructions: Enter your account details to proceed.

11. Keystone Bank

• Code: Dial 7111911#

• How it works: Input the requested details and block access instantly.

12. Unity Bank

• Code: Dial 77999*Phone Number#

• Example: If your number is 08012345678, dial 77999*08012345678#

• Alternative: Call 07080666000

13. Wema Bank (ALAT)

• Code: Dial 945911#

• Details: Follow the instructions to restrict your account.

14. Polaris Bank

• Code: Dial 833911#

• Note: You’ll be asked to verify some account info.

What Happens After You Block the Account?

Blocking your account means:

• No one can make withdrawals or transfers.

• USSD, mobile app, and card functions are deactivated.

• Your money is safe (at least for now).

But don’t stop there.

READ ALSO: Moniepoint USSD Code For Transfers, Airtime, Data, Balance Check, and More

What to Do Next

Blocking is just the first step. Here's what to do next:

1. Visit the nearest branch ASAP.
   To properly secure or reopen your account, you must bring a valid ID (driver’s license, NIN, voter’s card, etc.).

2. Request for a new ATM card or SIM swap (if necessary).

3. Change your passwords, PINs, and login details.
   Especially if your phone or device was compromised.

4. Report any unauthorised transactions.
   Most banks will investigate and may refund fraudulent debits if reported promptly.

5. Enable security alerts.
   Make sure your SMS/email alerts are working to track future activity.

Save Your Bank’s USSD Block Code Now

You don’t want to be Googling USSD codes in a panic. Save your bank’s USSD code as a contact, name it “Block GTB” or “Access Bank Lock,” for example. Also, teach your family or friends how to do this. One day, that little knowledge could save someone’s life savings.

In a world where fraudsters are getting smarter, protecting your money is no longer optional; it’s essential. These USSD codes are fast, free, and effective. So even if you lose your phone, don’t lose your cool—dial the code and shut things down immediately.

Your money, your rules.