SIM card fraud can expose mobile users to serious risks because a phone number is often linked to banking, UPI, email and other digital services. These seven checks can help Indian users identify unauthorised connections, suspicious messages and possible telecom fraud before losses occur.
Why SIM security matters for Indian mobile users
Your SIM card is more than a way to make calls. A mobile number is commonly used to receive OTPs, authenticate online accounts and communicate with banks, payment services and government platforms. If criminals misuse a mobile connection or obtain control of a number, the consequences can extend beyond unwanted calls and messages.
SIM-related fraud can involve different methods. A fraudster may attempt to obtain a mobile connection using someone else’s identity documents, persuade a victim to share an OTP, impersonate a telecom or government official, or use deceptive messages to make the victim install malicious software.
The Department of Telecommunications (DoT) has created Sanchar Saathi to give consumers tools for checking mobile connections issued in their names and reporting suspected fraudulent communications. Its services include TAFCOP, which helps users identify mobile connections registered under their name, and Chakshu, which allows suspected fraud communications to be reported.
1. Check all SIM cards registered in your name
One of the most useful checks is to find out how many mobile connections are registered using your identity documents.
The DoT’s TAFCOP service, available through the Sanchar Saathi platform, allows subscribers to check mobile connections issued in their name. The government says the service can also be used to report connections that the user does not recognise or no longer requires.
This matters because consumers may have forgotten about old numbers, secondary SIM cards or connections obtained years earlier. An unfamiliar number should not automatically be assumed to be fraudulent, but it deserves investigation.
If you find a connection that you never obtained, use the reporting facility provided through Sanchar Saathi rather than ignoring it. The government has previously reported large-scale action against suspected fraudulent and unauthorised mobile connections through the platform.
Consumers should make this check periodically, particularly after changing mobile operators, replacing lost SIM cards or sharing identity documents for telecom-related services.
2. Never share an OTP for SIM activation or KYC
An OTP should be treated like a password for a specific transaction or authentication step. A legitimate telecom representative should not need you to disclose an OTP over a phone call simply because they claim your SIM is about to be blocked.
Fraudsters may use urgent stories such as KYC expiry, mobile disconnection, SIM replacement or account verification to pressure consumers into revealing codes. The DoT has specifically identified fraudulent communications involving claims about KYC updates, SIM or mobile-number disconnection and impersonation of officials among the types of suspicious communications consumers can report through Chakshu.
If someone asks for an OTP, stop the conversation and independently contact your telecom operator through its official customer-care channel.
Do not click a link sent by an unknown caller to complete a supposed KYC update. Do not install an application because a caller says it is required to keep your SIM active.
3. Watch for sudden loss of mobile network
A sudden and unexplained loss of mobile connectivity can have several harmless causes, including network outages, device problems or local coverage issues. But if your SIM stops working unexpectedly and you have not changed anything, it is worth checking with your telecom operator.
One possible concern is SIM-swap or SIM-replacement fraud, where a criminal attempts to get a replacement SIM associated with another person’s mobile number. A successful takeover can potentially interfere with SMS-based authentication and other services linked to the number.
The loss of network by itself does not prove that a SIM swap has occurred. However, if it happens alongside unexpected account alerts, unexplained OTP messages or banking notifications, act quickly.
Contact your telecom operator through an official channel and ask whether a replacement SIM or other change was recently requested for your number. If financial transactions are involved, contact your bank immediately and report suspected fraud.
4. Report suspicious calls, SMS and WhatsApp messages
Indian consumers do not have to simply ignore every suspicious message. The Sanchar Saathi portal includes Chakshu, a facility for reporting suspected fraudulent communications received through calls, SMS and WhatsApp.
The DoT says Chakshu covers suspected communications associated with cybercrime and financial fraud, including impersonation, fake KYC requests, mobile-number disconnection claims and fraudulent requests related to services such as banking, wallets, gas and electricity.
This is particularly useful when a message looks suspicious but you have not yet lost money.
For example, a message might claim that your SIM will be deactivated unless you complete KYC immediately. Instead of following the link, consumers can independently verify the claim and report the suspicious communication.
The important distinction is that Chakshu is intended for reporting suspected fraud communications. If you have already become a victim of cybercrime or financial fraud, you should also use the appropriate cybercrime reporting mechanism.
5. Keep your Aadhaar and identity documents under control
Mobile connections are issued using identity verification, so consumers should be careful about where and why they provide identity documents.
Do not casually send photographs of identity documents to unknown WhatsApp numbers or individuals claiming to arrange a SIM, KYC update or telecom service. If documentation is genuinely required, verify the organisation and use its authorised process.
Consumers should also avoid leaving photocopies of identity documents with unverified agents. When a document must be submitted, check what information is required and why.
The DoT’s Sanchar Saathi system was developed partly to help consumers detect mobile connections obtained using their identity documents. Its TAFCOP service specifically addresses connections registered in an individual’s name.
6. Check your phone’s IMEI if you suspect device-related fraud
SIM security and handset security are closely connected. A SIM can be moved between compatible devices, while the handset itself has a separate identifier called an IMEI.
The government-operated Sanchar Saathi CEIR service allows consumers to check the genuineness of a mobile handset using its IMEI. The IMEI can be displayed by dialling *#06# on the device. The government also provides an SMS-based verification option by sending KYM <15-digit IMEI number> to 14422.
This check is especially useful when buying a second-hand smartphone. Sanchar Saathi advises consumers to avoid devices shown as blacklisted, duplicate or already in use.
If your phone is lost or stolen, CEIR also provides a mechanism to request blocking of the handset. This is separate from blocking or replacing the SIM itself.
7. Act immediately if money is lost through a SIM-related scam
If a SIM-related scam has already resulted in unauthorised banking, UPI or other financial transactions, do not wait to see whether the situation resolves itself.
Contact the relevant bank or financial service immediately and report the transaction. You should also report cyber financial fraud through India’s National Cyber Crime Reporting Portal or by calling the national cybercrime helpline at 1930. The official portal states that 1930 is available for immediate reporting of cyber financial fraud.
If the issue concerns a suspicious phone number, website, WhatsApp account, SMS or social-media URL, the National Cyber Crime Reporting Portal also provides a facility for reporting suspected cybercrime-related identifiers.
Save evidence before deleting anything. Keep screenshots, phone numbers, messages, transaction references, emails and relevant bank alerts. These details can help when making a complaint.
Key Takeaways
- Use Sanchar Saathi’s TAFCOP facility to check mobile connections registered in your name.
- Never disclose an OTP to someone calling about SIM replacement, KYC or mobile-number verification.
- Report suspicious calls, SMS and WhatsApp messages through the government’s Chakshu facility.
- If a SIM-related scam causes financial loss, report it immediately through 1930 and the National Cyber Crime Reporting Portal.
FAQs
1. How can I check how many SIM cards are registered in my name?
Use the TAFCOP service available through the Government of India’s Sanchar Saathi platform. It allows subscribers to view mobile connections issued in their name and report connections they do not recognise.
2. What should I do if my SIM suddenly stops working?
First, contact your telecom operator through its official customer-care channel to determine whether there is a network outage or a change involving your number. If you suspect an unauthorised SIM replacement, inform the operator immediately and check connected banking and payment accounts for unusual activity.
3. Can I report a suspicious SIM-related message online?
Yes. The DoT’s Chakshu facility on Sanchar Saathi allows consumers to report suspected fraudulent communications received through calls, SMS and WhatsApp.
4. What number should I call after losing money in a cyber fraud?
For cyber financial fraud, call the national cybercrime helpline at 1930 as soon as possible and submit the complaint through the National Cyber Crime Reporting Portal.