DLT registration · India
DLT registration and TRAI’s calling rules, explained.
This page is about India. Since February 2019, businesses that send commercial SMS or make commercial calls through Indian telecom operators have worked inside TRAI’s Telecom Commercial Communications Customer Preference Regulations, 2018 (TCCCPR), and their blockchain-based register: DLT, short for distributed ledger technology.
DLT is where the business, its sender IDs, message templates, customers’ consent and their do-not-disturb choices are recorded, and where operators check commercial traffic before delivery. TRAI amended the rules in February 2025 and again in September 2026. Below is where they stand in November 2026, with links to TRAI’s own documents. It is general information, not legal advice.
TCCCPR 2018 · Amended Feb 2025 & Sept 2026 · 140 · 1600 · 1601 · Sources: trai.gov.in · Not legal advice
- System00:00
Pre-dial · 140-series number · real estate not blocked in the preference register
- AI agent00:00
Namaste, this is Meera, an AI assistant calling from Northgate Homes about the 2BHK flats you asked about on our website. Is this a good time?
- Caller00:07
We have already booked elsewhere. Please do not call again.
- AI agent00:11
Understood. We will not call you about this again. Have a good day.
- System00:15
Opt-out recorded · number suppressed for future campaigns
What DLT registration covers.
TCCCPR came into force on 28 February 2019. It is co-regulatory: TRAI sets the objectives, and the access providers, India’s telecom operators, run the DLT platforms that enforce them.
- 01Register the entityThe business, and any telemarketer it uses, registers with an operator.
- 02Headers and numbersSender IDs for SMS; 140-series numbers for promotional calls.
- 03TemplatesEvery SMS content template is registered before use.
- 04Consent and preferencesExplicit consent and DND choices sit on the ledger.
- 05ScrubbingMessages are checked against template, consent and preference.
- 06Delivered or blockedAnything that fails a check does not go through.
- Who registers
- The principal entity (PE) is the business sending the communication. Registered telemarketers (RTMs) connect senders to operators. Both register with an access provider.
- What DLT records
- Customer preferences, consent acquisition and verification, complaints, registered entities and content templates.
- Unregistered means unsolicited
- Since February 2025, commercial communication from a sender not registered with any operator is treated as unsolicited commercial communication.
- The detail lives with operators
- Each access provider’s Codes of Practice set the exact procedure, forms and documents for its DLT platform.
140, 1600 and 1601: which number makes which call.
In India the number on the screen tells the person what kind of call it is. The “160-series numbers” people search for are the 1600xx and 1601xx ranges, kept for service and transaction calls.
| Who calls from it | For which calls | DND and spam tagging | |
|---|---|---|---|
| 140xx | Senders in any sector, registered with an operator under TCCCPR | Promotional calls | Blocking a sector, or all promotion, on the DND register stops 140-series calls from that sector. Other tagging or filtering is not allowed. |
| 1600xx | Entities regulated by RBI, SEBI, IRDAI and PFRDA; government bodies | Service and transaction calls to existing customers; government-to-citizen communication | Tagging, blocking or filtering 1600-series calls is not permitted. |
| 1601xx | Utilities, logistics and courier companies, in the first phase from TRAI’s Direction of 10 August 2026 | Service and transaction calls | A designated series: the September 2026 amendment bars operators from flagging it as suspected spam. |
| Ordinary 10-digit numbers | Any subscriber | Not for telemarketing: the February 2025 amendment restricts senders from using them for it. Many service calls still come from them. | Can be flagged as suspected spam by operators’ detection systems. Automated calls from them must be declared in advance (see below). |
As stated by TRAI in Press Release 91/2026 (10 July 2026), Press Release 11/2025 (12 February 2025) and the Third Amendment of 18 September 2026. General information, not legal advice. · Source: TRAI Press Release No. 91/2026
DLT registration, step by step.
The order most senders follow. Each operator’s DLT portal sets its own forms and documents.
- 01
Register as a principal entity
Register your business on an access provider’s DLT platform. Since the February 2025 amendment, registration includes physical verification, biometric authentication and linking a unique mobile number. Telemarketers acting for you register too.
- 02
Register your headers
Headers are the sender IDs on your SMS, and commercial SMS can only go out on registered headers. Each now carries a suffix that tells the reader its type: -P promotional, -S service, -T transactional, -G government.
- 03
Register content templates
Every message must match a registered template, with fixed and variable parts, filed under the right category. The September 2026 amendment adds penalties for templates registered under the wrong one.
- 04
Get the right numbers for calls
Promotional calls go out only from 140-series numbers. Regulated BFSI entities and government bodies use 1600-series numbers for service and transaction calls; utilities, logistics and courier companies use 1601-series.
- 05
Declare automated calls
Under the September 2026 amendment, a sender must tell its originating operator in advance that it makes application-to-person (A2P) calls, including robo-calls and pre-recorded or artificial voices, with the number ranges it will use. The declaration is recorded on DLT, and undeclared A2P calls count as unsolicited. This takes effect sixty days after the amendment’s publication in the Gazette.
- 06
Record consent, honour opt-outs
Explicit consent is acquired digitally and verified with the customer by OTP. Promotional messages must carry an opt-out, and after someone opts out a sender may not ask them for consent again for 90 days.
DND registration: what customers can block.
Most people call it DND, some still say NCPR. Under TCCCPR it is the preference register on DLT, and promotional calls and messages are checked against it before delivery.
Commercial calling in India, in TRAI’s numbers.
TRAI published these figures with its September 2026 amendment. They show why automated calling is now where the rules are tightening.
- Commercial SMS a day
- 250 crore
About 2.5 billion commercial messages a day, on average, January to April 2026.
- 140-series calls a day
- 15 crore
About 150 million calls a day from 140-series numbers over the same months.
- Disconnections that were A2P lines
- 75%
15,736 of 20,591 disconnections for violations in April 2026 were SIP or PRI connections used for automated calls.
Figures from the explanatory memorandum to the Telecom Commercial Communications Customer Preference (Third Amendment) Regulations, 2026, notified 18 September 2026. The 75% share is TRAI’s rounding. · Source: TRAI, TCCCPR (Third Amendment) Regulations, 2026
India’s TRAI rules next to the US TCPA.
For teams calling both countries. India registers senders, numbers and templates up front; the US sets rules on consent and conduct and enforces them through the FCC and the courts.
| India: TRAI, TCCCPR 2018 | United States: FCC, TCPA | |
|---|---|---|
| Do-not-call | DND preference register, by sector, set on 1909 or the TRAI DND app | National Do Not Call Registry; lists scrubbed against a copy no more than 31 days old |
| Promotional calls | Only from 140-series numbers | No designated number series; no calls before 8 a.m. or after 9 p.m. local time |
| Consent | Explicit consent recorded on DLT, verified with the customer by OTP | Prior express written consent for telemarketing with an artificial or prerecorded voice |
| AI and automated voices | A2P calls, including artificial voices, declared in advance to the operator (September 2026 amendment) | AI-generated voices are “artificial” voices under the TCPA (FCC 24-17, February 2024) |
| Opt-out | Promotional messages carry an opt-out; no new consent request for 90 days after one | Automated opt-out on artificial-voice telemarketing calls; revocations honoured within ten business days |
| Enforcement | First violation: outgoing services barred for 15 days. Repeat violations: every telecom resource disconnected across operators for a year, and the sender blacklisted | Private lawsuits of $500 to $1,500 per violation; FCC penalties |
India: TCCCPR as amended to September 2026; enforcement as summarised in TRAI Press Release 11/2025. US: 47 CFR § 64.1200 and 47 U.S.C. § 227 as of Nov 2026; detail on our TCPA compliance page. Not legal advice. · Source: TRAI Press Release No. 11/2025
Where VocalLabs fits, and what stays yours.
DLT entries, headers, templates and number series belong to the sender, with its operator. VocalLabs is the agent on the call, and these are the controls it gives you to run inside the rules you are bound by.
- 01Telephony
Your numbers, your carrier
Run each campaign from the 140 or 1600 numbers registered to you. VocalLabs connects to your telephony over SIP trunks or cloud numbers.
- 02Pre-dial
Checks before the dial
Numbers are checked against your suppression list and the national registry before dialling.
- 03Opt-out
Opt-outs that stick
An opt-out spoken on the call is honoured in every future campaign.
- 04Hours
Calling hours you set
Calling hours and retries for unanswered calls are set per campaign.
- 05Follow-up
DLT-registered SMS follow-up
Follow-ups go out on WhatsApp or DLT-registered SMS while the call is fresh.
- 06Data
India routing
VocalStack Voice offers India data routing, consent tones and real-time PII redaction.
Questions buyers ask first.
Your registrations. Our agent on the call.
Tell us your sector, the number series you hold and who you need to reach. We will set up the agent on your telephony, with your calling hours, suppression list and follow-ups, and run a pilot batch with you listening.
