Hyderabad: The Department of Telecommunications (DoT) has issued clear orders for messaging and communication apps. From January 1, 2027, apps such as WhatsApp and Telegram must follow SIM-binding rules. This means a user's account must be linked to an active SIM card with their registered Indian mobile number. If the linked SIM is not in the phone, these apps will not work.

The aim is to stop cyber fraud and keep the digital system safe. The rule may change how people use these apps. Until now, many people have used WhatsApp and Telegram on phones that do not hold the SIM of that number. From the next year, they will no longer be able to do so.

Order and deadline

DoT issued the order on November 28, 2025 under the Telecom Cyber Security Rules 2024. The government made it public on December 1, 2025 through a Press Information Bureau release. Apps were first given 90 days. After industry requests, the deadline was extended to December 31, 2026. From January 2027, all apps must follow the rules.

The order names eight app: WhatsApp, Telegram, Snapchat, Arattai, ShareChat, Josh, JioChat, and Signal. The rules apply to all app-based communication services that use an Indian mobile number to identify users or provide a service.

How SIM binding will work?

With SIM binding, a messaging ap will stay linked only to the active SIM that holds the registered number. If the SIM is taken out of the phone or switched off, the app will stop working. To follow the rule, service providers will have to take new steps, such as blocking account access once the SIM is removed or deactivated.

Many apps now keep working even after the registered SIM is taken out. DoT says this gives fraudsters a chance. They can misuse Indian mobile numbers even from outside the country. 

For the web and desktop versions of these apps, there was earlier a rule to log out every six hours. The government has now chosen a risk-based approach. This means users will be logged out only when needed, and not otherwise.

Apps such as WhatsApp are already getting ready. Reports say WhatsApp is working on a SIM check feature for Indian users. The app will tell users that checking the SIM card is needed to meet rules.

Why the rule is needed and how it affects users?

The government has pointed to digital arrest scams, impersonation, phishing, investment fraud and loan scams. In December 2025, DoT released data showing that cyber fraud caused losses of more than Rs 22,800 crore in India in 2024. Banking and UPI services already use SIM-linked checks, and the same model is now coming to messaging apps.

Most people will notice little change, as they already use these apps on the phone that holds their registered IM. However, some may face trouble. Many people change phones often, remove SIM cards, switch numbers or travel a lot. Others use WhatsApp on another phone or tablet while the SIM sits in a different phone. They will no longer be able to do this, as the registered SIM must be active and fitted in the same device that runs the app.