Quick answer
What is business messaging for SaaS & Technology?
SaaS messaging means sending SMS, OTP and WhatsApp messages from your software through an API: sign-up verification, two-factor authentication, product alerts and billing reminders. What matters is a simple API, reliable delivery, status webhooks and protection against OTP fraud.
Last updated: 21 October 2026
Software products send messages from code: verifying users, alerting them about events and nudging them to pay or come back. What matters is a clean API, reliable delivery and clear status webhooks.
Key facts
- ✓SMS to Indian numbers needs DLT registration even when sent from software.
- ✓Every API message returns an ID; delivery status is posted to your webhook.
- ✓SMS pumping fraud inflates OTP costs through fake sign-ups; rate limits are the main defence.
- ✓WhatsApp authentication templates support one-tap and copy-code buttons for OTPs.
- ✓TRAI requires URLs and callback numbers in SMS templates to be whitelisted on DLT.
The SaaS & Technology messaging journey
- 1
Sign-up
Verify phone numbers with an OTP during registration.
- 2
Security
Use OTP for 2FA, new-device logins and sensitive actions.
- 3
Product events
Alert users about events in their account, such as approvals or failures.
- 4
Billing
Remind about renewals and failed payments with a link to update the card.
SaaS & Technology use cases by moment
| When | Message | Channel |
|---|---|---|
| Sign-up | Phone verification OTP | SMS OTP, WhatsApp OTP |
| Login from new device | 2FA code and security alert | SMS OTP |
| Account event | Approval, failure or threshold alert | WhatsApp, SMS |
| Trial ending | Reminder with upgrade link | WhatsApp, email |
| Payment failed | Prompt to update payment method | SMS + WhatsApp |
| Support ticket | Status updates and replies |
Which channel for what
Sample message templates
Examples in DLT format, where each {#var#} is filled in when the message is sent. Register your own wording on DLT before sending; we review templates during onboarding.
- {#var#} is your {#var#} verification code. It expires in 10 minutes. - {#var#}
- New login to your {#var#} account from {#var#}. Not you? Secure it: {#var#} - {#var#}
- Your {#var#} subscription renews on {#var#}. Manage billing: {#var#} - {#var#}
- Payment for invoice {#var#} failed. Update your card: {#var#} - {#var#}
Compliance for SaaS & Technology
- Register your entity, header and each template on DLT before sending SMS in India.
- Keep API keys on your server and rotate them if exposed.
- Collect only the phone data you need and allow users to delete it, in line with the DPDP Act.
Metrics to track
- OTP delivery time and verification success rate
- Cost per verified user
- Share of OTP requests blocked as suspected fraud
- Webhook delivery and processing time
- Failed-payment recovery rate
How to get started
- 1
Share your use case
Tell us which messages you send, on which channels, and your monthly volume.
- 2
Register on DLT
We help you register your entity, headers and templates; WhatsApp and RCS senders are set up in parallel.
- 3
Test
Send test messages from the panel or with sandbox API keys.
- 4
Go live
Start sending and track every message with live delivery reports.
SaaS & Technology FAQs
How do we stop SMS pumping fraud on our sign-up OTP?
Rate-limit OTP requests per number, IP and device, block abnormal number ranges, and verify before sending to premium destinations.
Do we need DLT as a software company?
Yes, for SMS to Indian numbers. Register your entity, header and each template you send.
Can delivery status come back to our system?
Yes. Every message gets an ID, and status events are posted to your webhook.
Should we use SMS or WhatsApp OTP?
Offer both: SMS reaches every phone, WhatsApp OTP can be cheaper and supports one-tap autofill. Use automatic fallback between them.
How do we test before going live?
Use sandbox keys to send to your own numbers, then switch to live keys once templates are approved.
What's an idempotent retry?
Retrying a failed API call with the same request ID so a network error doesn't send the message twice.
Can we receive inbound replies by API?
Yes. WhatsApp and two-way SMS replies are posted to your webhook.
Do you support international numbers?
Yes, on request per country. Tell us your destinations and we'll confirm coverage and rates.