Your phone rings. The number starts with 140. You pick up, and someone wants to sell you a credit card, a loan or an insurance plan. The next day, a call from a number starting with 1600 says it's your bank. Should you trust it?
Both series exist because India's telecom regulator, TRAI, wants you to be able to tell who is calling and why before you answer. Here is what the two series mean, what you can do about the 140 calls you never asked for, and where a caller ID app fits in.
What is the 140 number series?
Numbers starting with 140 are given to registered telemarketers for promotional calls: offers, sales pitches and marketing. If a number begins with 140, the caller is telling you, by law, that this is a sales call.
That's useful. A 140 call is rarely urgent, so you can decide whether you want to answer at all.
What is the 1600 number series?
The 1600 series is for service and transaction calls from banks, financial institutions and other regulated businesses: things like payment alerts, loan servicing or a call about your account. TRAI ordered commercial banks to move these calls to 1600 numbers by 1 January 2026. Other banks and NBFCs, mutual funds, pension bodies, stockbrokers and insurers followed between February and March 2026.
So when your bank calls about your account, you should increasingly see a number that starts with 1600. A bank "officer" calling from an ordinary 10-digit mobile number is a reason to be careful.
Is every 1600 call genuine?
A 1600 number is a good sign, not a guarantee. Whoever calls, the old rules still apply:
- Never share an OTP, PIN, CVV or password on a call. A real bank will not ask for them.
- If something feels wrong, hang up and call the number printed on your card or on the bank's official website.
- Don't install an app or open a link because a caller asked you to.
How to stop 140 sales calls
Under TRAI's rules, the way to stop 140 calls is Do Not Disturb (DND). In July 2026 TRAI said that 140 calls may not be tagged or filtered except by blocking them on the DND registry, and that 1600 calls may not be tagged, blocked or filtered at all. Since its September 2026 amendment, caller ID and spam apps may not blanket-block or spam-tag these series either. You can still block any number on your own phone.
Turn on DND
- Call or SMS 1909 from your mobile number and follow the steps to block all promotional calls, or only some categories.
- Or use the TRAI DND app, or your operator's app or website (Jio, Airtel, Vi and BSNL all offer it).
DND can take a few days to start working. The exact SMS wording and timings vary by operator, so follow what 1909 or your operator's app tells you.
Complain about calls that ignore DND
Since TRAI's 2025 rule changes, you can complain about spam calls and messages even if you haven't registered for DND. Use the TRAI DND app or 1909, and complain soon after the call. TRAI's September 2026 amendment also lets you appeal if you're unhappy with how a complaint was handled. Reporting matters: TRAI has reminded people that blocking a number on your own phone doesn't stop the sender, but complaints can.
Why spam calls continue after DND
DND works on registered telemarketers using the 140 series. Many unwanted calls don't come from them at all. They come from ordinary 10-digit mobile numbers: unregistered telemarketers, loan agents and outright scammers. DND can't recognise those calls, which is why your phone may still ring with "loan offers" after you've switched DND on.
For those calls you need two things: complain about them, and know who's calling before you answer.
Where BharatCaller fits
BharatCaller is a free Indian caller ID and spam-blocking app. For the calls above, here is what it does:
- Caller ID and spam warnings: before you answer, you see the name behind an unknown 10-digit number and whether it's known for spam. That covers the calls DND can't reach.
- Blocking on your phone: block any number you never want to hear from again.
- For 140 calls, DND with your operator is the way to stop them, as described above.
Quick answers
Why is a 140 number calling me?
A registered telemarketer is making a promotional call. If you don't want these, register for DND by calling or messaging 1909.
Can I block 140 numbers in my phone's settings?
You can block a single number, but 140 calls come from many numbers. DND is the rule-based way to stop them.
Should I answer a 1600 call?
It's meant for genuine service calls from banks and other regulated businesses. Answer if you're expecting it, but never share an OTP, PIN or password, and call your bank's official number if in doubt.
Can caller ID apps tag or block 140 and 1600 calls?
No. TRAI's amendment of September 2026 bars call management apps, such as caller ID and spam apps, from blanket-blocking, filtering or spam-tagging calls from the 140, 1600 and 1601 series. You can still block any number on your own phone.
