What Is a 1600 Phone Number?
A 1600 number is a phone number that only banks, NBFCs, insurance companies, pension fund managers, and government departments are allowed to use in India. They call you from it for things like OTPs, payment alerts, loan updates, or policy reminders. No other type of business can get one. TRAI, India’s telecom regulator, set up this series so people can tell a real bank call apart from a scam call, just by looking at the number.
Is a call from a 1600 number safe, or is it spam?
It’s safe. A 1600 or 1601 number can only be used by an entity that has registered with the telecom department and got the number allocated to it. These numbers are meant purely for service calls, so a bank isn’t allowed to sell you a new credit card or loan on this number. That’s reserved for the 140 series.
Caller ID apps such as Truecaller also treat 1600 numbers differently from random mobile numbers, so they usually don’t get flagged as spam or telemarketing, unlike a lot of the promotional calls you might get on a normal 10-digit number.
Still, common sense applies. Your bank will never ask for your card PIN, CVV, or OTP on a call, no matter what number it comes from. If a 1600 number call asks for that, hang up and call your bank back using the number on your card or app, not a number the caller gives you.
What 1600 numbers are used for
- Sending you a one-time password (OTP)
- Confirming a payment, transfer, or transaction
- Reminding you about an EMI, premium, or bill due date
- Giving you an update on a loan application or insurance claim
- Calling you back after you raise a support ticket
- Verifying your identity during KYC
Most of this volume is OTPs, since that’s the single biggest reason banks and NBFCs call or message customers. Businesses that already run their SMS and voice OTP delivery through a compliant provider usually have less rework to do when they add the 1600 series on top.
How the numbering works
A 1600 number has 10 digits and always starts with either 1600 or 1601.
- 1600 numbers go to government departments and public sector organisations.
- 1601 numbers go to private and public entities regulated by RBI, SEBI, IRDAI, or PFRDA, which covers banks, NBFCs, mutual funds, stockbrokers, insurers, and pension fund managers.
The digits right after 1600 or 1601 tell you the telecom circle and which operator issued the number. Because of that, one number usually only works for one circle. A bank calling customers all over India needs a separate 1600 or 1601 number for each circle it operates in, not just one number for the whole country.
1600 vs 140, 1800, and a normal mobile number
Here’s how it stacks up against the other number types businesses in India use:
| Series | What it’s for | Who can use it | Can it be used for marketing |
|---|---|---|---|
| 1600 / 1601 | Service calls: OTPs, KYC, payment alerts, policy updates | BFSI entities and government bodies only | No |
| 140 | Telemarketing and promotional calls | Any business registered on DLT | Yes, that’s what it’s for |
| 1800 | Toll-free customer support (inbound) | Any business | Not applicable, it’s for incoming calls |
| Normal 10-digit mobile | General business calling | Any business, but banks and NBFCs can’t use it for service calls anymore | Was used for both earlier, now restricted |
The two series don’t mix. If a call to confirm your OTP also tries to sell you a new product, that call is supposed to come from 140, not from a 1600 number. Using a 1600 number for that isn’t allowed.
Why TRAI brought in the 1600 series
For years, scammers called people pretending to be from a bank, using an ordinary mobile number, and there was no way to check if the call was real. TRAI’s fix was to give banks, NBFCs, insurers, and government bodies one number range that nobody else is allowed to use. A call from your bank now comes from a 1600 or 1601 number. Anything claiming to be your bank from a different kind of number is the one to check twice.
TRAI has said that around 485 entities and over 2,800 numbers were already on the 1600 series before the mandate came in. SBI Card is one of the early adopters.
TRAI’s deadlines for the 1600 series
TRAI issued the main Direction on 19 November 2025, laying out deadlines for entities regulated by RBI, SEBI, and PFRDA. A separate Direction for IRDAI-regulated insurance entities followed on 16 December 2025. All of the deadlines below have now passed, and TRAI has said none of them will be extended. The full text is on TRAI’s official notifications page.
| Regulator | Entity category | Deadline |
|---|---|---|
| RBI | Commercial banks (public, private, foreign) | 1 January 2026 |
| RBI | Large NBFCs (asset size above ₹5,000 crore), Payments Banks, Small Finance Banks | 1 February 2026 |
| RBI | Remaining NBFCs, Co-operative Banks, Regional Rural Banks, smaller entities | 1 March 2026 |
| SEBI | Mutual funds and asset management companies | 15 February 2026 |
| SEBI | Qualified stockbrokers (identified annually by exchanges) | 15 March 2026 |
| SEBI | Other registered intermediaries | Voluntary, after verification |
| PFRDA | Central Recordkeeping Agencies and Pension Fund Managers | 15 February 2026 |
| IRDAI | Insurance sector entities | 15 February 2026 |
Every entity in this table should already be on the 1600 or 1601 series. Calling customers from a normal 10-digit number for OTPs or account alerts is a compliance gap right now, not a future risk, and TRAI or the entity’s own regulator can act on it.
What happens if a business hasn’t switched yet
Two things happen. First, telecom operators can block calls that don’t come from a registered 1600 or 1601 number, which means OTPs and alerts stop reaching customers. Enforcement has been getting stricter through 2026 as the deadlines pass, so this risk grows the longer a business waits. Second, the regulator overseeing that business (RBI, SEBI, IRDAI, or PFRDA) can treat it as a compliance failure of its own, separate from whatever action TRAI takes.
There’s a slower cost too. As more banks and insurers move to the 1600 series, people start expecting service calls to come from it. A call from a normal mobile number starts looking suspicious by comparison, even for businesses that haven’t switched yet. Waiting just means fewer people pick up.
How to get a 1600 or 1601 number
- Check you’re eligible. Only entities regulated by RBI, SEBI, IRDAI, or PFRDA, or government bodies, can apply.
- Register on the DLT platform. You’ll need to register your entity details and your call headers.
- Get a number for each telecom circle you call into, not just one for all of India.
- Set up delivery through a SIP trunk, PRI, or an internet telephony provider, depending on your existing setup.
- Keep your call flows separate: service calls go on 1600 or 1601, marketing calls stay on 140.
- Move your systems over in phases, IVR, dialer, OTP gateway, instead of switching everything on the same day.
Most companies don’t build this from scratch. They run calls through a telephony provider that already takes care of DLT registration, DND checks, and call recording rules. This guide on scaling voice infrastructure for regulated industries walks through what that setup looks like in practice.
How Exotel can help?
You can run 1600, 140, and your regular DIDs together in the same channel set, so your operations keep running without a scramble around each entity’s cutover date.
Splitting number series across different vendors is where most of the actual pain shows up. If OTPs run through one provider and marketing calls through another, you’re managing separate dashboards, separate DLT and DND settings, and separate reporting for each, and every new number series means onboarding another vendor. Keeping 1600, 140, and your existing DIDs on one platform means one place to manage headers, templates, and call routing, and your OTP gateway or dialer doesn’t need to be rebuilt each time a series changes.
Exotel holds a Unified License Virtual Network Operator (UL VNO) license, so it can activate 1600 numbers quickly and integrate them with your existing IVR and CRM.
The usual bottleneck is getting numbers provisioned circle by circle and then wiring them into call flows that are already live, not the DLT registration itself. A UL VNO license lets Exotel allocate 1600 numbers directly across circles instead of going through a reseller layer, which is where a lot of the delay usually sits. And because the numbers plug into your existing IVR and CRM, you’re swapping which number a call comes from, not rebuilding the flow, the agent scripts, or the CRM logic behind it.
Frequently asked questions
Is a 1600 number toll-free?
No. Toll-free numbers are the 1800 series, used for inbound customer support. 1600 numbers are for outbound service calls from banks, insurers, and government bodies.
Can a business call me for marketing on a 1600 number?
No. Marketing and sales calls have to come from the 140 series. A 1600 number is only allowed to carry service calls, like OTPs or payment alerts.
Why did I get a call from a 1600 number?
Most likely your bank, NBFC, insurer, or a government office is trying to reach you about an OTP, a payment, a claim update, or a KYC check. It’s not a random telemarketer, since 1600 numbers can’t be used for that.
Are calls from 160 numbers spam?
No, they’re the opposite of spam. The whole point of the series is to separate bank and government calls from spam and scam numbers. Caller ID apps generally don’t flag them as spam either.
What’s the difference between 1600 and 1601?
1600 is for government departments and public sector bodies. 1601 is for private and public entities regulated by RBI, SEBI, IRDAI, or PFRDA, like banks, NBFCs, and insurers.
Do 1600 numbers work the same everywhere in India?
No. Each number is tied to a telecom circle. A business that operates across the country usually needs a different 1600 or 1601 number for each circle.
Is DLT registration required for a 1600 number?
Yes. Every entity using the series has to register its details and call headers on the DLT platform. That’s what makes each call traceable back to a verified organisation.
What happens if a business still hasn’t switched?
Its calls can get blocked by telecom operators, and its regulator can treat it as a compliance issue on top of that. Every deadline has already passed, so this is already happening rather than something to plan for. Customers also tend to trust calls from a normal mobile number less now that 1600 numbers are becoming the norm.
The 1600 series fixes a real problem: too many scam calls pretending to be from a bank. Customers get a simple way to tell their bank’s calls from a scammer’s. Compliance teams get a migration project with fixed dates, so plan the DLT registration and number rollout well ahead of the deadline, not close to it.
