Many Indian customers still prefer a phone call. A recorded voice reminder in Hindi can reach people who rarely read SMS, an IVR menu can route hundreds of enquiries to the right team, and a missed-call number can capture leads from newspaper ads and hoardings. But spam and fraud calls have made customers wary, and TRAI has responded with stricter rules for business calling.
This guide explains the main voice services available to Indian businesses, the number series you must use, and a practical compliance checklist. It is based on TRAI publications as of October 2026.
The main types of business voice service
- Inbound IVR: customers call your number and hear a menu ("Press 1 for sales, 2 for support"), with calls routed to the right person or team, recorded and reported.
- Toll-free numbers: 1800 numbers where the business pays for the call, often used for customer care.
- Virtual or cloud numbers: numbers that ring on staff mobiles or a cloud phone system, with multi-agent routing and call recording.
- Missed-call services: customers give a missed call to register interest, request a callback or receive information by SMS.
- Outbound voice broadcast (robocalls or OBD): pre-recorded messages sent to many numbers, such as reminders, alerts or campaign messages, sometimes with keypad responses.
- Click-to-call and call tracking: calls from websites and ads, tracked to campaigns.
For a comparison of when to use each, see our guide to IVR vs voice broadcast vs call centre.
The rules for outbound business calls
India's rules for commercial calls come from TRAI's Telecom Commercial Communications Customer Preference Regulations, 2018 (TCCCPR), as amended in February 2025. The key points:
Promotional calls must come from the 140 series
Promotional voice calls, including promotional robocalls, must be made from the 140 number series allocated for telemarketing. TRAI directed operators to move 140-series telemarketing calls onto the online DLT platform by 30 September 2024 for better monitoring.
Service and transactional calls use the 1600 series
The 1600 series has been allocated by the Department of Telecommunications for service and transactional calls. In the first stage, it was earmarked for entities regulated by RBI, SEBI, IRDAI and PFRDA, such as banks, brokers, insurers and pension providers, with wider allocation possible later. The aim is to help customers recognise genuine service calls from financial institutions.
No telemarketing from ordinary 10-digit numbers
The PIB summary of the 2025 amendment states that senders are restricted from using normal 10-digit numbers for telemarketing, so that commercial communication comes from designated headers or number series. TRAI's press note on the amendment describes tough penalties for unregistered senders found making unsolicited commercial communication, including barring of outgoing services and, for repeated violations, disconnection of telecom resources and blacklisting.
Robocalls and auto-dialers
Under the amendment, promotional calls through auto-dialers or robocalls are permitted only through 140-series numbers, while service and transactional robocalls may use the 1600 series or other series allotted for that purpose. Senders must also notify their originating access provider in advance about the use of auto-dialers or robocalls.
DND preferences and timing
Promotional calls must respect customers' Do Not Disturb preferences, which customers set through the TRAI DND app, their operator or the 1909 short code. Promotional communication is generally allowed only between 10 AM and 9 PM. Our India voice compliance overview summarises these points.
What this means in practice
If you run promotional voice campaigns (for example, a real estate launch or an admission campaign), they must go through a registered telemarketer using 140-series numbers, with DLT registration and DND scrubbing. Your sales staff should not cold-call prospects about offers from personal mobiles.
If you are a bank, NBFC, broker or insurer, expect to use 1600-series numbers for service and transactional calls, and check the latest instructions from your regulator and operator.
If you send service calls such as appointment or payment reminders, keep a clear record of the customer relationship or consent, and keep the message strictly service-related. Adding an offer turns a service call into a promotional one.
Inbound IVR, toll-free and virtual numbers are about customers calling you, so the outbound telemarketing rules apply less directly. But if staff use these numbers to make outbound promotional calls, the promotional rules apply.
Designing an IVR customers actually like
A good IVR saves time; a bad one drives customers away. Tips:
- Keep the menu short: three or four options at the first level is plenty
- Offer languages early: "Hindi ke liye 1 dabaiye, for English press 2" works well in many Indian markets
- Put the most common option first, based on your call data
- Always offer a way to reach a person
- Route by time: after hours, offer a callback request or WhatsApp link
- Record and review calls (with an announcement that calls may be recorded) to train staff and improve scripts
- Follow up missed calls quickly, ideally automatically by SMS or WhatsApp
Writing effective voice broadcast messages
- Keep recorded messages short, ideally under 30 seconds
- State who is calling in the first few seconds
- Use simple Hindi, English or the local language your customers prefer
- Give one clear action: press a key, call back or check SMS
- Avoid sounding like a scam: no urgency tricks, no requests for OTPs or bank details
Choosing a voice service provider in India
Ask providers:
- Are you a registered telemarketer on DLT, and which number series will my calls use?
- How do you handle DND scrubbing and the promotional time window?
- Can you provide IVR, toll-free, virtual numbers and outbound campaigns on one platform?
- What reports do you provide (answered, unanswered, duration, keypresses)?
- How are calls charged: per minute, per pulse, or per answered call?
- Do you integrate with my CRM, WhatsApp and SMS?
Measuring voice campaign results
Voice campaigns should be judged on outcomes, not just call counts. Useful measures include:
- Answer rate: how many calls were answered, by time of day and day of week
- Listen-through rate: how many people heard the full message
- Keypress responses: how many pressed a key to confirm, request a callback or speak to an agent
- Callbacks and conversions: bookings, payments or sales that followed
For inbound IVR, track call volumes by menu option, abandoned calls, waiting times and missed calls. These numbers show where you need more staff, a simpler menu or better self-service options, such as sending a WhatsApp link with information instead of keeping callers on hold.
How DND Teams helps
DND Teams provides IVR, virtual numbers, missed-call services and compliant voice broadcast campaigns for businesses across India, from our base in Bhopal to clients in Delhi, Mumbai and beyond. We help design IVR menus, record scripts in Hindi and English, set up compliant promotional and service campaigns, and connect calls to SMS and WhatsApp follow-ups. See our voice call services or contact us for a free review of your calling setup.
Rules for commercial calls in India continue to evolve, so check the latest TRAI and DoT instructions or ask your provider before major campaigns.
Get a custom quote
Working with clients in India, the US, UK, Canada, Australia and the UAE, DND Teams replies with a short written review and a clear quote, with no obligation. Get a custom quote for IVR, virtual numbers or voice campaigns, or message us on WhatsApp at +91 88274 09728.
Not ready for a full project? Start with our IVR starter for US$149 (one-time, paid in advance). Price covers our setup work only. Platform, number, call-minute and carrier charges are billed separately at cost. Need more? Get a custom quote. See how our pricing works for what affects your price.
Prices shown are indicative ranges in US dollars and exclude taxes and third-party charges (such as Meta or carrier fees, billed at cost) unless stated. Your price depends on your requirements; get a custom quote for an exact figure. This article is general information, not legal advice, and reflects our understanding as of October 2026.