How to stop spam calls and marketing messages

Unwanted marketing calls can be reduced by registering your preference and reporting offenders. Fraud calls need a different response.

Source. The pages on unsolicited commercial communication of the Department of Telecommunications' Sanchar Saathi portal, read on 12 November 2026. The rules themselves are the Telecom Commercial Communications Customer Preference Regulations, 2018, of the Telecom Regulatory Authority of India (TRAI).

Spam or fraud? Tell them apart first

• Spam (unsolicited commercial communication) is marketing you did not ask for: loans, credit cards, property, coaching, insurance. It is a nuisance.
• Fraud tries to take your money or details: fake KYC, electricity disconnection, parcel, police, prize. It is a crime.

Spam is handled through your preference registration and complaints. A fraud attempt should be reported on Chakshu as "suspected fraud", and a fraud that cost you money goes to 1930. See Sanchar Saathi.

Step 1: register your preference (Do Not Disturb)

A telecom subscriber can block all commercial communications, or block them selectively by category. The official modes of registering are:

• the TRAI DND app;
• an SMS to the short code 1909;
• a call to 1909;
• your telecom service provider (its app, website or customer care).

Operators must keep this facility available round the clock. Preferences can be set by category of communication, by mode (call or SMS), by time band and by day of the week. The exact SMS keywords for each choice are listed by TRAI and by your operator; the DND app and your operator's app let you choose from a menu instead.

Messages about your own transactions and services, such as bank alerts and OTPs, are not blocked by this preference.

Step 2: report the ones that still come

You can complain about spam received by voice call or SMS that is against your consent or registered preference through:

• Chakshu on the Sanchar Saathi portal or app ("Report Spam (UCC)");
• an SMS or a call to 1909;
• the TRAI DND app;
• your telecom service provider.

Complain soon: the regulations treat prompt complaints as valid complaints for investigation, while late ones are taken only as reports that help find repeat spammers. The Chakshu page shows a window of 30 days. Complaints are passed to the telecom operators for action against the sender, and you receive a complaint ID that can be tracked with your operator.

To report on Chakshu: open sancharsaathi.gov.in, choose Citizen Centric Services, then Chakshu, pick the medium and category, enter the details (a screenshot is optional), verify your number by OTP and submit.

Reading the sender name on an SMS

Genuine business messages come from a header: a sender name of up to eleven characters, not an ordinary ten-digit number. The portal describes the usual pattern as two letters, a hyphen and the header, such as XY-ABCDEF, where the first letter stands for the telecom operator and the second for the service area. Information about who owns a header can be looked up at TRAI's sender information site, smsheader.trai.gov.in.

What this tells you:

• A message claiming to be from your bank or electricity company but sent from a ten-digit mobile number is almost certainly fraud.
• A proper header is a good sign, but not proof. Still judge the message by what it asks: no genuine sender asks for your OTP, PIN or an app install.

What you can do on the phone itself

• Android (Google Phone app): Phone › three dots › Settings › Caller ID and spam › turn on "See caller and spam ID" and "Filter spam calls". Google Messages has "Spam protection" under its settings.
• iPhone: Settings › Apps › Phone › Silence Unknown Callers sends calls from numbers not in your contacts to voicemail and the recent calls list. Messages has "Filter Unknown Senders".
• WhatsApp: Settings › Privacy › Calls › Silence unknown callers. See WhatsApp privacy settings.
• Block and report individual numbers from the call log or the message.

Menu names differ a little between phone makers and versions.

Habits that reduce spam at the source

• Do not give your main number at shops, malls, parking counters and lucky-draw forms unless it is truly needed.
• Untick "send me offers" when signing up for apps and loyalty cards, and read what you are consenting to.
• Do not reply to spam, and do not press keys on recorded marketing calls.
• Use a second number or an email address for sign-ups you do not care about.

Independent guide. This is not a government, bank or police website. Helplines and rules were checked at official sources on 12 November 2026; confirm on the official site before relying on them.