An old SIM may still be linked to your National Identity Card even when you no longer use the number. In a worse case, a number you do not recognize may appear under your NID. Checking the list takes only a minute and can prevent a much larger identity or account-security problem.

Here is the official BTRC method for checking mobile numbers registered under your NID in Bangladesh, plus the steps to take if the result looks wrong.

Official method at a glance

Step What to do
1 Use a mobile number that is already registered under your NID.
2 Dial *16001#.
3 Enter the last four digits of your NID when prompted.
4 Wait for an SMS showing numbers registered under that NID across operators.

These steps are published on the official BTRC NEIR Citizen portal. Use the USSD code yourself rather than giving your NID digits to a shop, stranger or social-media page.

Before you start

You need access to at least one active mobile number registered with your own NID. The check uses the last four digits of the NID as verification. It does not require the full NID number to be sent by SMS.

If the USSD menu does not appear, confirm that you dialled from the correct SIM, check the network signal and try again later. For persistent problems, contact your operator through an official channel.

How to read the result

The reply should identify the mobile numbers registered under your NID across operators. Some digits may be masked for privacy. Compare the entries with:

  • Your current primary and secondary numbers
  • Old SIMs kept at home
  • Numbers used by close family members with your knowledge
  • SIMs that were lost, damaged or abandoned
  • Any number you cannot explain

Do not ignore an unfamiliar entry simply because it is inactive. A number associated with your identity can create trouble if it is misused.

What to do if you find an unknown SIM

  1. Save the result. Take a screenshot or write down the masked number and operator.
  2. Contact that operator. Use its official helpline or visit an authorized customer-care centre.
  3. Take your original NID. Ask the operator to identify the registration and explain the process for removing or blocking an unauthorized SIM.
  4. Keep the complaint reference. Record the date, service centre and ticket or acknowledgement number.
  5. Escalate when necessary. If you suspect fraud or identity misuse, contact the appropriate authorities and preserve all evidence.

Do not try to call or threaten the user of an unknown number. The registration may be an old mistake, a recycled number or deliberate misuse; the operator and authorities are better placed to investigate.

Check after losing a phone or SIM

If a SIM is lost, contact the operator promptly to block it. An active SIM may receive password-reset or transaction codes. Our lost or stolen phone checklist explains the correct order for securing the device, mobile wallet and accounts.

After replacing or closing the SIM, run the NID check again later to make sure the operator’s records match your expectation.

SIM security habits worth keeping

  • Never hand over your NID copy without a clear purpose.
  • Write the purpose and date on a photocopy when appropriate.
  • Never tell anyone an OTP, PIN or mobile-wallet code.
  • Use official operator stores and helplines.
  • Check the NID-linked number list periodically.
  • Block a lost SIM quickly, even if the phone itself is inexpensive.

Scammers often create urgency and claim that a SIM, wallet or account will be closed. Pause and verify through the official app or number. Our guide on avoiding bKash and mobile-banking scams covers the most common warning signs.

IMEI check and SIM check are different

A SIM registration check answers: “Which mobile numbers are linked to my NID?” An IMEI check answers: “What is the registration or validity status of this handset?”

For an IMEI check, the NEIR portal instructs users to send KYD, a space and the 15-digit IMEI to 16002. For a complete explanation, read our official-phone and NEIR guide.

Frequently asked questions

What is the code for checking SIMs under an NID?

The BTRC NEIR Citizen portal currently instructs users to dial *16001# from a number registered under the NID and then enter the last four NID digits.

Can I check using somebody else’s SIM?

The official process says to dial from a mobile number registered with the NID being checked. Use your own registered number and do not share your NID details with others.

Will the SMS show all operators?

BTRC says the reply includes mobile numbers registered under the NID across all operators.

Where can I remove an unauthorized SIM?

Contact the relevant operator through its official helpline or customer-care centre. Bring the identity documents it requires and keep a complaint reference.

Information checked against the BTRC NEIR Citizen portal on 23 August 2026.