The Indian government has made SIM card linkage mandatory starting January 1, 2027. This means that popular messaging applications such as WhatsApp and Telegram will not be able to function on a smartphone without an installed SIM card.
The Ministry of Telecommunications issued relevant directives, requiring platforms to integrate accounts with active SIM cards used for registration by December 31, 2026. If the SIM card is removed, replaced, or deactivated, the application's functionality will cease until a valid SIM card is reinstalled.
The main goal of this step is to combat cross-border cyber fraud, phishing, and digital arrest schemes that use Indian phone numbers, as well as to enhance overall cybersecurity in the telecommunications sector.
Apple has introduced changes to iOS by releasing a software patch that helps detect the operation of iPhones without a physical SIM card to comply with the new rules. It is reported that the Signal service has not yet responded to the government's notifications.
Starting January 1, messaging services must ensure that a registered SIM card is installed in the device. This will likely affect users of WhatsApp or Telegram who use Wi-Fi without a registered SIM card, as well as those who use multiple devices or frequently change their SIM cards.
Previously, in November, the Ministry of Telecommunications (DoT) issued rules after discovering that some application-based communication services using Indian numbers for customer identification allowed users to use the services without having a basic subscriber identification module (SIM) in the device. This feature was exploited for cyber fraud, especially from outside the country.
To stop this threat, many government agencies insisted on the mandatory implementation of SIM card linkage. Subsequently, the DoT issued instructions to major application-based communication services in accordance with the Telecom Cybersecurity Rules (TCR) 2024. These services include WhatsApp, Telegram, Snapchat, Arattai, Sharechat, Jiochat, and Signal.
Now, communication app providers must ensure that their service 'is continuously linked to a SIM card (linked to the mobile phone number used to identify customers/users or to provide or deliver services) installed in the device, making it impossible to use the application without this specific, active SIM card.' Furthermore, they must ensure that 'the web instance of the mobile application, if provided, logs out periodically (no later than six hours) and provides the user with the option to re-link the device using a QR code.'