SIM binding starts January 1, what happens to WhatsApp, Telegram? Explained in 5 points

SIM binding is going to take effect from January 1, 2027. Going forward, you may only access apps like WhatsApp and Telegram if the registered SIM is in the phone. Here is what this means.

In Short

• Accounts must remain linked continuously to active, KYC-verified registered SIM cards
• Wi-Fi-only tablets, frequent SIM changers and overseas travellers may face disruptions
• The directive remains unclear about how eSIM-enabled devices will be treated

SIM binding is set to be mandatory from January 1, 2027. The Department of Telecommunications (DoT) has confirmed messaging apps must verify that the mobile number associated with an account is linked to the SIM installed on that phone. That is, if you are using WhatsApp on your smartphone, the SIM with your WhatsApp number must be in that phone.

This move may change how you use apps like WhatsApp and Telegram. Today, you can access these apps on devices with just a WiFi connection once you have logged in. The rules may particularly impact those who travel abroad, change SIMs, or devices, frequently, or rely mainly on WiFi.

So how will this work? And what happens if your SIM card is not in the device you use? Here is everything you need to know.

1. What is SIM binding?

SIM binding, in essence, means that the SIM card linked to your accounts must be installed in the phone that you use. The DoT issued a directive for SIM binding on November 28, 2025. As per the directive, messaging apps, like WhatsApp and Telegram that use Indian mobile numbers to identify users, need to verify that the account remains linked to the corresponding SIM installed in the device.

Currently, you can verify a number through a one-time password, or OTP, and continue using an app even after the SIM is removed, deactivated or transferred to another device. But this changes with the rules. For instance, if you were using WhatsApp on your tablet while the SIM for that account was in your smartphone, WhatsApp would no longer work.

Do note that banking and payment apps already use SIM binding. And you cannot make online payments via UPI or online transfers if the linked SIM in not installed in your phone.

2. How will it work?

To enforce SIM binding, messaging apps will have to check whether the registered SIM remains active and available in the phone. The original directive named Under WhatsApp, Telegram, Snapchat, Arattai, ShareChat, Josh, JioChat and Signal among the covered services.

Messaging apps will have to ensure that the SIM linked to the account remains installed in that device. Though it is unlikely that accounts stop working automatically on the deadline, it will depend on how individual apps enforce it.

Platforms have until December 31, 2026, to link accounts continuously with the active, KYC-verified SIM associated with the registered mobile number.

3. What happens to WhatsApp, Telegram and other apps?

As said earlier, WhatsApp and Telegram users may have to keep their registered SIM cards available in their phones. WhatsApp has reportedly begun beta-testing SIM binding on Android, while Apple released an iOS software update in September to help detect when an iPhone does not have a SIM card. The precise restrictions will depend on how each platform implements the directions.

Coming to web sessions such as WhatsApp Web, the original rules also required web sessions to be logged out at least once every six hours. Then you would have to re-link your device through a QR code. But the DoT later withdrew the blanket six-hour logout requirement and replaced it with risk-based logouts, including immediate termination in suspected fraud cases. You should, therefore, not assume that WhatsApp Web will automatically log them out every six hours.

4. What about eSIMs and WiFi-only devices?

SIM binding directives issued by the DoT focus on keeping an account linked to the active SIM associated with the registered number. However, the order does not specify what happens to phones with eSIMs installed. It is likely that you would need to have your eSIM installed in the device if you want to use your linked account. But there is no specific word on it just yet.

The rules are more likely to affect people using messaging apps on WiFi without the registered SIM, including those using WiFi-only tablets. They could also affect accounts used across several devices or operated outside India, while you are on a trip for instance.

5. Why is the rule being introduced?

The DoT has raised concerns that the current systems pose risks for cybercrime. Without SIM binding, messaging accounts can continue operating after the associated SIM has been removed or deactivated. Long-running web and desktop sessions can also allow an account authenticated in India to be operated remotely without fresh verification.

According to the department, this gap has been exploited for phishing, impersonation, investment and loan scams, as well as digital arrest fraud.

Cyber-fraud losses exceeded Rs 22,800 crore in 2024, according to the government. SIM and device binding, already used by banking and payment apps, is intended to improve the traceability of Indian numbers and prevent account takeovers and remote misuse. The DoT also plans a mobile number verification platform to identify legitimate phone numbers.

- Ends