The Telecom Regulatory Authority of India (TRAI) has blacklisted more than 21 lakh mobile numbers and nearly one lakh entities involved in spam and fraudulent communication over the past year, marking one of the largest crackdowns on telecom misuse in recent years. The Ministry of Communications said the scale of action highlights how user reporting through the official TRAI DND app has become central to identifying and disconnecting offenders across the country.

According to the advisory, reporting spam via the DND app enables TRAI and telecom operators to trace, verify and permanently disconnect rogue numbers. In contrast, blocking a number on a personal device only hides the call for one user and does nothing to stop scammers from targeting others by switching numbers. Officials said the coordinated response was possible only because citizens consistently flagged spam through the official system rather than relying solely on device-level blocking.

Once a spam call or SMS is reported on the DND app, the complaint is routed to the concerned telecom service provider. After verification, the number is either disconnected or blacklisted from the network. The process has helped dismantle large spam clusters, many operated by organised fraud networks. The Ministry said the enforcement drive is backed by technology-led monitoring, improved data-sharing systems, and closer coordination between telecom operators and cybercrime agencies.

Public advisory: What users must do?

TRAI has urged all mobile users to adopt safer communication practices. Citizens have been advised to:

• Download the TRAI DND app from official app stores
• Report spam calls and SMS through the app rather than blocking numbers on devices
• Avoid sharing personal or banking details on calls, messages or social media
• Immediately disconnect suspicious or threatening calls
• Report cyber frauds to the National Cybercrime Helpline 1930 or cybercrime.gov.in
• Report telecom-related fraud attempts using Sanchar Saathi’s ‘Chakshu’ feature

Officials said these steps are crucial to stopping spam “at the source” and preventing scammers from exploiting vulnerable users.

TRAI said the advisory is particularly important for senior citizens, women and digitally new users, who are often targeted by scammers. The regulator has appealed to the public to stay alert, share the advisory widely and report any suspicious communication without delay. The Ministry added that the regulator remains committed to maintaining a safe, secure and trustworthy telecom ecosystem, with continued enforcement and citizens’ participation forming the backbone of the anti-spam strategy.