Every channel misses some people. A number may not be on WhatsApp. An email address may bounce. A customer may have opted out of SMS promotions but still be happy to hear from you on Arattai. Smart fallback is a simple idea: when a message cannot get through on one channel, send it on the next one you choose, once, and only to the people who missed it.
How it works
You set an order, for example WhatsApp, then Arattai, then SMS, then email. For each contact:
- The first channel that can reach them is used. A contact without a phone number skips straight to email.
- If that message fails later, for example WhatsApp reports the number is not on WhatsApp, the next channel takes over automatically.
- Optionally, if a message is still not delivered after a few hours, the next channel is tried too.
Each person receives the message on one channel. Nobody gets four copies.
Why it matters
- Coverage. TRAI reported over 1,155 million mobile connections in India in September 2026, not counting machine SIMs. Not every one of those people uses the same apps, but nearly every phone can receive an SMS.
- Cost. Meta charges for delivered WhatsApp templates, so you do not pay for messages that fail. Fallback lets you spend on the channel that actually works for each person.
- Experience. Customers get time-sensitive information, such as a delivery or an appointment, on a channel they read.
Choosing an order
There is no universal best order. A few patterns work well:
| Goal | Suggested order |
|---|---|
| Rich updates with images and buttons | WhatsApp, Arattai, SMS |
| Critical alerts | WhatsApp, SMS, email |
| Long content such as invoices or newsletters | Email, WhatsApp |
| Lowest cost reminders | Email, then SMS only if not opened |
What to watch
- Consent per channel. Opting in on one channel is not consent for all of them. Keep separate opt-ins and respect each.
- Different templates. WhatsApp, Arattai and DLT SMS each need their own approved template. Prepare them before you rely on fallback.
- Timing. Fallback hours should match the urgency. An OTP fallback should happen in seconds, a newsletter fallback can wait a day.
How SG Reach helps
SG Reach supports smart fallback in three places: as a Smart send step in chatbot flows, as a step type in drip sequences, and as an option on WhatsApp and Arattai campaigns. Every attempt is logged in Automation activity, so you can see which channel finally reached each customer.
Sources
Figures are from the sources above as of the date of this article. Platform rules and prices change, so check the latest version before you rely on them.
WhatsApp, email, SMS and Arattai campaigns and automation in one place.