The best SMS gateway in India for most small businesses is Fast2SMS or MSG91 if price is the priority, and Exotel or Gupshup if you also need voice or WhatsApp from the same provider. On official pricing, Fast2SMS charges ₹0.25 per SMS at the ₹100 starting recharge, falling to ₹0.11 on very large recharges, and MSG91 lists ₹0.25 per SMS for 5,000 messages, falling to ₹0.16 at higher volumes. Exotel shows SMS "starting at ₹0.18" on its pricing page, with exact rates depending on your account. Whichever you pick, every business SMS in India must be registered on the DLT platform first, or it will not be delivered.
SMS and OTP gateway prices compared
| Provider | Published price per SMS (India) | Minimum | Best for |
|---|---|---|---|
| Fast2SMS | ₹0.25 (₹100 to ₹3,999 recharge) down to ₹0.11 (₹6 lakh+ recharge) | ₹100 recharge | Small businesses, low-cost OTP and alerts |
| MSG91 | ₹0.25 (5,000 SMS) down to ₹0.16 (9,62,500 SMS); custom deals from ₹0.13 | 5,000 SMS pack | Developers wanting OTP APIs and a dashboard |
| Exotel | Listed as starting at ₹0.18; exact rate set per account | Via sales or plan | Businesses also using Exotel for calls |
| 2Factor | Not verified; the official site blocked our checks | Check official site | OTP-focused API users |
| Gupshup | Quote-based | Quote | SMS + WhatsApp + RCS at scale |
| Kaleyra | Quote-based | Quote | Banks and large enterprises |
| Twilio Verify | Priced per verification on Twilio's site | Pay as you go | Global apps needing OTP in many countries |
| Airtel IQ | Quote-based | Quote | Enterprises wanting a telecom operator direct |
Prices exclude GST. Operators also add a DLT scrubbing charge (see below).
How DLT works (and why your OTPs fail without it)
TRAI's rules on commercial communication require every business that sends SMS in India to register on a DLT (Distributed Ledger Technology) portal run by the telecom operators. According to Exotel's DLT guide, you must register:
- Your business as a Principal Entity. You get a Principal Entity ID, which must be passed with every message.
- Your header (sender ID). This is the six-character name shown to the customer, such as the short form of your brand.
- Every message template. Templates must include your brand name. OTP templates without a brand name became invalid in 2020, and Template ID enforcement went live on 1 April 2021.
- Consent where the message type requires it.
You register once on any operator's DLT portal, and it works across operators. Your SMS provider then links your Entity ID, headers and template IDs. A message whose text does not match an approved template is rejected.
DLT scrubbing charge
Exotel's support documentation states that operators apply a DLT scrubbing charge of ₹0.025 per SMS unit on transactional and promotional SMS, in addition to the provider's SMS rate, from 1 September 2020. Ask your provider whether its quoted rate already includes this.
Message length and billing
One SMS unit holds 160 characters of plain English text or 70 characters of Unicode (for example Hindi or Marathi). Longer messages are split into parts, and each part is billed as a separate SMS. Exotel's documentation also says messages rejected by DLT scrubbing or DND filtering are not charged.
SMS types in India
- OTP / service implicit: login codes, payment confirmations and delivery updates. These can reach numbers on DND.
- Transactional / service explicit: messages the customer has agreed to receive.
- Promotional: offers and marketing. These do not reach DND numbers and can only be sent during permitted hours.
A good OTP sender keeps OTP traffic on a separate, high-priority route so it is not slowed down by bulk promotional traffic.
Fast2SMS
Fast2SMS's official pricing page uses recharge-based slabs that apply to promotional, transactional, service, OTP and API messages:
- ₹100 to ₹3,999: ₹0.25 per SMS, unlimited validity.
- ₹4,000 to ₹7,999: ₹0.21 per SMS.
- ₹8,000 to ₹13,999: ₹0.19 per SMS.
- ₹14,000 to ₹59,999: ₹0.17 per SMS.
- ₹60,000 to ₹1,29,999: ₹0.15 per SMS.
- ₹1,30,000 to ₹5,99,999: ₹0.13 per SMS.
- ₹6,00,000 and above: ₹0.11 per SMS.
Discounted slabs have a validity period, after which the rate goes back to ₹0.25 for any remaining credit.
Good for: shops, schools and small apps that want to start with a ₹100 recharge.
MSG91
MSG91's pricing page lists India SMS rates by pack size: ₹0.25 for 5,000 SMS, ₹0.20 for 16,500, ₹0.18 for 30,000, ₹0.17 from 60,000 to 4,50,000, and ₹0.16 for 9,62,500. MSG91 says custom pricing can go down to ₹0.13 per SMS. It also offers a dedicated OTP product, SendOTP by MSG91, with retry and voice fallback.
Good for: developers who want clean APIs, OTP widgets and delivery reports.
Exotel SMS pricing
Exotel's pricing pages show SMS "starting at ₹0.18", and its developer documentation states that exact rates depend on SMS type, volume tier and message length, and are shown in your account dashboard or by sales. Because the full rate card is not public, treat ₹0.18 as a starting point, not a guaranteed price.
Good for: businesses that already use Exotel for calls and want one vendor, one wallet and one set of APIs.
Other OTP SMS service providers in India
- 2Factor: an OTP-focused Indian API provider. Check current pack prices on its official site.
- Gupshup: SMS, WhatsApp and RCS (Gupshup RCS) at enterprise scale. Quote-based.
- Kaleyra: used by banks and large enterprises. Quote-based.
- Twilio and Twilio Verify: best when your app verifies users in many countries, not only India.
- Airtel IQ: buy messaging directly from a telecom operator.
- Kutumb SMS by MyOperator: an option if you already use MyOperator for calls.
Browse the full list in SMS marketing software.
How to choose an SMS or OTP gateway
- Estimate your monthly volume. Price slabs only matter once you know whether you send 2,000 or 2 lakh messages.
- Ask for the all-in rate. Confirm whether the rate includes the DLT scrubbing charge and GST.
- Check OTP speed and delivery reports. Ask for delivery-time statistics and test with numbers on Jio, Airtel, Vi and BSNL.
- Look for fallback. Voice OTP or WhatsApp OTP fallback helps when SMS is delayed.
- Check credit validity. Cheap slabs often expire. Buy what you will use.
- Get DLT sorted first. A provider that helps you register headers and templates saves days.
- Plan for WhatsApp. Many businesses now send OTPs and updates on WhatsApp as well. See WATI vs Interakt vs AiSensy.
FAQs
What is the best SMS gateway in India?
For low cost, Fast2SMS and MSG91 publish the clearest per-SMS prices. For businesses that also need calling or WhatsApp, Exotel and Gupshup are strong choices. The best one depends on your volume and whether you need APIs.
How much does one SMS cost in India?
Published rates start around ₹0.25 per SMS for small packs and fall to between ₹0.11 and ₹0.16 at high volumes (Fast2SMS and MSG91 pricing pages), plus GST and the DLT scrubbing charge.
What is Exotel's SMS pricing?
Exotel shows SMS starting at ₹0.18 on its pricing page. The exact rate depends on your account, SMS type and volume, and is confirmed by Exotel sales or in your dashboard.
Is DLT registration mandatory for OTP SMS?
Yes. Under TRAI's rules, businesses must register their entity, sender ID headers and message templates on a DLT portal. Unregistered OTP messages are blocked.
What is an OTP sender?
An OTP sender is the service, usually an SMS API, that generates or delivers one-time passwords to users' phones. It is also used to mean the six-character header the customer sees as the sender name.
Do OTP messages reach DND numbers?
Yes. OTPs and other service messages can reach numbers on the Do Not Disturb list. Promotional SMS cannot.
