Stop Spam Calls in India: DND, Filters and Complaints

The short answer

Start with DND: dial the toll-free number 1909 or sign up through the TRAI DND app (your OTPs and other transactional SMS will keep arriving). Next, switch on the spam protection built into your phone. Whenever an unwanted sales call or SMS still gets through, lodge a complaint within 7 days using 1909, the TRAI DND app or your operator’s app. Attempts to cheat you belong on Chakshu (Sanchar Saathi), and if money has already gone, dial 1930.

There is no one switch that ends spam for good. DND keeps registered telemarketers away, your operator and handset label a good chunk of what’s left, and complaints are what trigger action against the senders.

Spam calls are rarely the reason people walk into Mobivault. It usually comes up while we’re setting up someone’s new phone.

In this article10 sections

Register for Do Not Disturb (DND) with TRAI
Let your mobile operator flag spam for you
Switch on your handset’s own spam protection
Blocking one particular number
How to file a complaint against a spam call or SMS
Send fraud calls and messages to Chakshu
Reading official number series and SMS headers
Seeing the caller’s name: CNAP
Common questions
Sources

Register for Do Not Disturb (DND) with TRAI

TRAI’s official term for DND is preference registration. It lets your operator know which commercial calls and SMS from registered senders you’d rather not get, for example calls from 140-series numbers and SMS whose header ends in -P. You’re free to change your choices whenever you like.

From the number you want covered, call 1909 and go through the voice menu.
Another route is the TRAI DND app for Android and iPhone: confirm your number with an OTP, then block every promotion or just selected categories.
You can also go through your operator. In MyJio, the path is Profile → Settings → Service settings → Do not Disturb. Vi customers can use the Vi app or myvi.in/dnd, and Airtel offers a DND page on airtel.in that works with an OTP.
Hold on to the confirmation SMS, since it carries your reference number.

According to Jio, the change kicks in within 24 hours. Vi’s code of practice promises to acknowledge your request within 15 minutes and put it into effect within 24 hours.

Note: Sending an SMS to 1909 works too. The texts named in TRAI’s rules are BLOCK PROMO for all promotions and BLOCK 1 to BLOCK 8 for a single category each. The operators’ help pages, however, still carry older keywords: START 0 appears on Jio’s help page and Airtel’s blog, while Vi’s FAQ gives FULLY BLOCK. When in doubt, simply call 1909.

Picking the right DND setting

Setting	Gets blocked	Still allowed through
Block Promo	Promotional calls and SMS across all categories	Messages that are transactional, service-related or from the government
Category-wise (1 to 8)	Promotions, but only in the categories you select	All the rest
Fully Block (TRAI is withdrawing it)	Every promotional call and SMS, and also service messages you had consented to	OTPs and other transactional messages, government messages, and service messages from companies you’re already a customer of

Based on TRAI’s TCCCPR Second Amendment Regulations, 2025 and Third Amendment Regulations, 2026 (verified on 10 October 2026).

Fully Block is going away. The option is scrapped by TRAI’s Third Amendment, notified on 18 September 2026. That change comes into force 30 days after the amendment appears in the Official Gazette, and from then operators get 15 days to shift every Fully Block registration over to Block Promo. There’s nothing you have to do yourself. Block Promo will still keep out all promotions, though service messages will reach you.

DND has eight categories: banking, credit cards and insurance; property (real estate); education; health; automobiles and consumer goods; IT, communication, broadcasting and entertainment; leisure and tourism; and food and beverages. Apart from categories, blocking can also be set by mode (calls, SMS or robocalls), by time of day and by weekday.

Tip: OTPs are never stopped by DND, so if your codes aren’t turning up, the cause lies elsewhere; our guide on what to do when OTP SMS don’t arrive can help. Every promotional SMS also has to include a way to opt out, and once you opt out of a sender, it can’t seek your consent again for 90 days.

Let your mobile operator flag spam for you

TRAI stated in September 2026 that the big operators now run AI-based systems that spot suspected spam and warn customers. Mostly, all you get is a warning label; picking up the call is still your choice.

Airtel: calls and SMS that look like spam have carried a “Suspected SPAM” tag since September 2024. Airtel describes the service as free and active for every customer, without any app or request, and it flags malicious links inside SMS as well.
Vi: going by Vi’s Vi Protect page, the network on its own labels suspicious SMS “Vi Suspected SPAM” and suspicious calls “Suspected SPAM”, with no extra charge. You need a VoLTE phone for the call warning, while SMS flagging works on any handset. The Vi app also lets you report and block spam calls.
Jio and BSNL: we couldn’t find an official page explaining a spam label for calls. In October 2025, news reports said Jio had begun rolling out spam alerts for incoming calls. BSNL, for its part, said in an August 2025 announcement that suspicious SMS links are now blocked on its network, without you having to turn anything on.

TRAI’s position is that calls from its official 140 and 1600 series must never be tagged as spam. Its September 2026 amendment, once it takes effect, also stops the operators’ AI systems from flagging numbers in the 140xx, 1600xx and 1601xx ranges.

Switch on your handset’s own spam protection

Android: phones using the Phone by Google app

In the Phone app, go to More options (three dots) → Settings → Caller ID and spam.
Make sure See caller ID and spam is switched on. It comes enabled out of the box.
Enable Filter spam calls. Calls caught by it won’t ring or trigger a missed-call notification, though they remain listed in your call history. If your phone has automatic Call Screen, you’ll find spam blocking inside Call Screen instead.

To cover SMS, open Google Messages and tap your profile picture → Messages settings → Protection and safety → Spam protection, then confirm that Enable spam protection is on. On phones that support it, Google switches this on by itself.

On a Samsung Galaxy

Launch the Phone app and tap the three dots → Settings.
Enable Caller ID and spam protection, then tap Agree.
Now tap the Caller ID and spam protection entry itself, switch on Block spam and scam calls and choose either Only block high-risk scam calls or Block all spam and scam calls.

The Smart Call page on Samsung India’s site likewise directs you to Caller ID and spam protection in call settings. We took the names of the two blocking choices from Samsung’s Canada guide, so the wording on your model or One UI version might be a little different.

On an iPhone

Unknown callers: open Settings → Apps → Phone. If you’re on iOS 26 or later, set Screen Unknown Callers to Silence; on iOS 18, switch on Silence Unknown Callers instead. Such calls are sent to voicemail and remain visible in Recents.
Spam calls: on that same settings screen, enable the Spam filter (called Silence Junk Callers on iOS 18). It only works on calls your carrier labels as possible spam, and we couldn’t verify that any Indian operator provides this for iPhones, so don’t count on it.
Texts: with iOS 26 or later, go into Messages, tap the filter button → Manage Filtering and switch on Screen Unknown Senders. So that OTP alerts keep coming, tap Allow Notifications and enable the categories you need (the choices differ by region). On iOS 18 the setting lives under Settings → Apps → Messages → Filter Unknown Senders. Enabling Text Message Filter additionally sorts SMS from senders you don’t know into Transactions and Promotions.

Warning: Silencing unknown callers can hide real calls too, like a delivery agent or a clinic ringing you. Save the numbers you’re expecting to hear from, and look through your spam folder from time to time.

In our experience at Mobivault, silencing unknown callers suits older parents best. On the other hand, customers who regularly get calls from unfamiliar numbers, shopkeepers for instance, have missed real calls with it switched on. Use it only if your important calls mostly come from people already saved in your contacts.

What about Truecaller and other caller ID apps?

Apps like these mark spam based on what their users report. Before you install one, look at the permissions it asks for, such as access to your contacts or call log, and go through its privacy policy. Under TRAI’s rules, they aren’t allowed to tag or block 140 and 1600 numbers. Blocking any number yourself remains possible.

Blocking one particular number

Phone by Google: open your call history, tap the call and select Block / report spam. To undo it, go to Settings → Blocked numbers. The Unknown toggle on that screen only covers numbers that are private or hidden.
Samsung: Phone app → three dots → Settings → Block numbers, then key in the number or choose it from Recents or Contacts. While a call is coming in, tapping Block number also works.
iPhone: Phone → Recents, tap the info button beside the number and then Block Caller. Messages and FaceTime calls from it get blocked too. You can reverse this from Blocked Contacts in Settings (where it sits depends on your iOS version).

A block only prevents that one number from getting through to you. Since spammers keep changing numbers, lodge a complaint as well.

How to file a complaint against a spam call or SMS

In February 2025 TRAI revised its complaint rules. Every change listed here has been in force since mid-April 2025:

7 days to complain: you now get 7 days from the call or SMS (earlier it was 3). Anything filed after that is logged only as a report.
DND not required for unregistered senders: since telemarketers aren’t permitted to use regular 10-digit numbers, a sales call coming from an ordinary mobile number can be reported even if you never signed up for DND.
Registered senders: if you haven’t blocked a category on DND, promotions in it from 140 numbers and -P headers are permitted, so get registered before you complain.
What a valid complaint needs: the sender’s number or header, your own number, the date and a brief description.

Call 1909, or go to the spam (UCC) complaint option in the TRAI DND app or in your operator’s app or website.
Choose the relevant call or SMS from your log, or attach a screenshot instead (operator apps have to support this), and go over the details.
Submit it and note down the complaint ID so you can follow its progress.

The 2025 rules say that once 5 different people complain about an unregistered sender within 10 days, action begins: that sender’s outgoing services are suspended while the operator looks into it. A sender found at fault on a first violation has all outgoing services barred for 15 days, while repeat offenders have every connection cut for a year and get blacklisted.

Two more changes are coming from TRAI’s Third Amendment, notified on 18 September 2026. First, action may begin after complaints from just 3 different people within 10 days, provided the operator’s AI has flagged one of that sender’s numbers too. Second, you’ll be able to appeal the outcome of a complaint within 15 days of being told the result (or, if no result reaches you within 15 days, during the 15 days after that), using the same channels as for complaints. Neither applies yet: both take effect 90 days after the amendment’s publication in the Official Gazette.

Send fraud calls and messages to Chakshu

Fraud means someone is trying to cheat you. Typical examples are fake KYC or bill-payment messages, investment scams, job or loan offers, sextortion, bogus customer care, and callers posing as the police, CBI, TRAI or DoT. These should go to Chakshu, a Department of Telecommunications (DoT) service on Sanchar Saathi.

Go to sancharsaathi.gov.in/sfc, or use the Sanchar Saathi app, which lets you report directly from your call log or SMS.
Select call, SMS or WhatsApp along with the type of fraud, and add a screenshot.
Fill in the number or SMS header, the date and time (it has to be within the last 30 days) and a description that’s at least 30 characters long.
Give the number on which you received it, verify it with an OTP, accept the declaration and hit submit.

DoT says it cannot share what happened with individual reports. With WhatsApp, report the sender within WhatsApp as well. Sanchar Saathi is also the place to block a phone that’s lost or stolen.

Warning: Don’t use Chakshu for money you’ve already lost. If you’ve been cheated, immediately call the cyber crime helpline 1930 or file a report at cybercrime.gov.in, and get in touch with your bank.

Reading official number series and SMS headers

What shows up	What it tells you	Blockable with DND?
A call from a 140xx number	A registered business making a promotional call	Yes, in the sectors you’ve blocked
A call from a 1600xx number	Transactional or service call from a government body, bank, NBFC, insurer, mutual fund, broker or pension fund	No
A call from a 1601xx number	Transactional or service call from a courier or logistics company or a utility (electricity, water, gas or LPG); rollout under way since August 2026	No
SMS header with -P at the end	A promotion	Yes
SMS header with -S at the end	A service message	No (service messages sent on the strength of your consent are stopped only by Fully Block, which TRAI is withdrawing)
SMS header with -T at the end	A transactional message, OTPs for example	No
SMS header with -G at the end	A message from the government	No

Based on TRAI press releases and regulations (verified on 10 October 2026).

TRAI gave pension entities, insurers, mutual funds, qualified stockbrokers, banks and NBFCs deadlines falling between 1 January and 15 March 2026 to shift their service and transactional calls to 1600 numbers. That means you should be extra cautious when a caller on a regular 10-digit number claims to be from your bank or insurer, and you should never give out an OTP during a call.

In July 2025, COAI, the operators’ association, said every operator had added the -P, -S, -T and -G suffixes. You can look up which company owns a particular header on TRAI’s portal, smsheader.trai.gov.in.

Seeing the caller’s name: CNAP

With CNAP (Calling Name Presentation), the caller’s name appears on screen with no app needed. TRAI’s recommendation was to use the name given on the caller’s SIM application form. DoT’s stand, which TRAI noted in October 2025, is that the feature should be on by default, with the option of asking your operator to switch it off. DoT wants 4G and 5G users to get it first.

Operator pilots were reported by the trade press in November 2025, and since then operators have been enabling CNAP in phases. According to Vi’s help page, on Vi it works only with VoLTE phones and, for the time being, only on calls from other Vi numbers. At the time of writing (October 2026), we haven’t come across any official statement that it works across all networks or on calls between different operators. Take the name as a clue and nothing more: it shows whose name the SIM is registered in and says nothing about whether you can trust the call.

Mobivault shop note: If spam calls are bothering you, we’ll help you register for DND, either by calling 1909 or through the TRAI DND app, and we’ll switch on your phone’s spam filter before you leave the shop.

Common questions

Does DND block OTPs and alerts from my bank?

No. None of the DND options blocks OTPs or any other transactional message.

Why do spam calls keep coming even after I signed up for DND?

DND covers registered senders only. A sales call from a normal 10-digit number is itself against the rules, so file a complaint within 7 days and switch on your phone’s spam filter. Also, DND can need up to 24 hours before it starts working, and any business you’ve given digital consent to is still allowed to send you promotions.

Must I be on DND before I can complain?

Not when the sender is unregistered. For promotions from registered senders, you first need to block that category on DND.

Is there a way to block government messages?

No. TRAI’s rules don’t require consent for government messages (headers ending in -G), and DND offers no setting to block them.

Money is gone after a fraud call. Is Chakshu the right place?

No. Straight away, call 1930 or report at cybercrime.gov.in, and contact your bank. Chakshu is meant for reporting fraud attempts.

Stop Spam Calls and Texts in India: Your Guide to DND, Spam Filters and Complaints