DoTs SIM Binding Rule Explained: What It Means for Messaging Apps and Users

In a new SIM binding requirement, on December 1 the Department of Telecommunications announced it was moving towards stricter verification for messaging platforms. It provided messaging platforms with a 90-day window to implement the changes under the directive, and three months since the Directive was issued. rule, which seeks to ensure that messaging app accounts are always linked to an active SIM card at all times. In its policy, the policy seeks to address growing cases of digital impersonation, financial fraud, online scams and identity abuse through app-based messaging services. A group of internet activists has called on the DoT to recall its mandate for SIM binding in tehe country.

What Is SIM Binding?

The Department of Telecommunications has issued the new directive as an amendment to the T telecom Cyber Security (TCS) Rules, 2024. This is known as the Telecommunication Cyber Security (TCS) Amendment Rules, 2025 and has been notified of the new framework.

According to the law, message service must have a continuous SIM validation (in which user account is required to remain associated with the active SIM card that was present at the time of registration). Service providers had a 90-day period for the legislation to implement the law, .

Specifically, it is mandated to include messaging services that are classified as Telecommunication Identifier User Entities or TIUEs. Such services include WhatsApp, Telegram and Signal (as well as Snapchat & Messenger) popular messaging services. The term SIM binding, which is described as a way to ensure that the registered identity remains verifiable and associated with telecom subscriber records at all times.

This, the DoT said, is attempting to stop growing cases of digital impersonation, financial fraud, online scams and misuse of identity — all conducted through messaging apps. Criminals have been noted to be using the app’s feature that allows users to access the application even after the SIM is removed or deactivated, for example in case of number recycling.

The DoT announced mandatory SIM binding for messaging platforms, and Internet advocacy group Internet Freedom Foundation asked the Dot to recall the mandate after it was cited as having “some problems related to implementation of SIMbinding in the country.” IFF highlighted several issues, saying users would likely have to buy an international travel pack to access WhatsApp while abroad and that they may not be able to use their chats if their SIM is damaged.

How SIM Binding Works

According to the DoT, SIM Binding links the user’s messaging account with the SIM card currently inserted into smartphone. In this system, it ensures that the phone number used during account registration is active and verifiable through records of the telecom subscriber. The new system requires messaging applications to conduct ongoing verification checks with the user’s SIM card.

They also need service providers to take further steps, such as restricting access to a user’s account when their SIM card is deleted or changed.

This new rule will be largely expected to affect people who frequently switch devices, replace SIMs, travel internationally with inactive domestic numbers or use messaging apps across multiple devices. During the account registration process, users must keep their SIM active in the main smartphone that is used to continue using the messaging platforms. The number changes may require users to re-register in the app, or verify again if they are using .

How Apps Will Be Affected

Rules also include a requirement for automatic logout systems of secondary devices. The directive states that connected devices may be logged out occasionally and require new authentication from the main smartphone, which contains the registered SIM card.

In a case where the SIM is installed, WhatsApp Web users may have to log in again every six hours through the main device. These would apply to services like Telegram Desktop and other web or desktop messaging clients. By comparison, users can log into services and still use them even if they switch SIM cards or switch networks.

Precious examples of Messaging apps have already started to prepare for compliance. According to WhatsApp, it is said that WhatsApp has started working on SIM-binding-related features for users in India to comply with the DoT directive. The application, which is based on a feature tracker, will tell users that it must check to see whether the user’s SIM card is in their smartphone to meet regulatory requirements.