What Does *21* Do and How Can You Protect Yourself from Call Forwarding Scams?
Cyber fraudsters are increasingly using social engineering to trick people into enabling call forwarding on their phones. One of the most commonly misused codes is *21*, which activates unconditional call forwarding on supported mobile networks.
While call forwarding is a legitimate telecom feature, enabling it unknowingly can expose users to serious security risks, especially if fraudsters convince victims to forward calls to a number they control.
What Does *21* Do?
Dialling *21*PhoneNumber# activates Unconditional Call Forwarding (also called Call Divert) on supported networks.
- Every incoming call is automatically diverted.
- Your phone may not ring before the call is forwarded.
- The caller is connected directly to the forwarded number.
Although this feature is useful when you intentionally want calls redirected, it should never be activated using a phone number provided by an unknown person.
- Never dial telecom codes provided by unknown callers.
- Banks, telecom operators and government agencies will never ask you to activate call forwarding to resolve account issues.
How Scammers Misuse Call Forwarding
- Pretend to be bank officials.
- Claim there is a courier or KYC problem.
- Pose as telecom customer support.
- Ask victims to dial *21* followed by a number.
- Incoming calls are then diverted to the fraudster's phone.
Possible Risks
- Missing important calls.
- Voice OTPs may be exposed if a service delivers them through calls.
- Fraudsters may attempt account recovery using diverted calls.
- Privacy and security may be compromised.
Important: Many banks now use SMS or app-based authentication rather than voice OTPs, so call forwarding alone does not automatically give someone access to your bank account. However, it can still be abused as part of a broader scam.
Useful GSM Codes
| Code | Purpose |
|---|---|
| *#21# | Check whether unconditional call forwarding is enabled. |
| ##21# | Cancel unconditional call forwarding. |
| ##002# | Erase most call forwarding settings on supported networks. |
Safety Tips
- Never follow instructions from unknown callers to dial special telecom codes.
- Verify any request directly with your bank or telecom operator.
- Regularly check your call forwarding status.
- Enable app-based two-factor authentication wherever possible.
- If you suspect fraud, immediately disable call forwarding and contact your telecom provider and bank.
Related Queries
- What does *21* do on Android and iPhone?
- How do I check if my calls are being forwarded?
- Can call forwarding be used in phone scams?
Disclaimer: GSM service codes may vary depending on your mobile operator and country. Call forwarding does not by itself allow someone to access all your accounts, but it can be exploited in certain fraud schemes. Always verify requests from unknown callers before dialing any service codes.
