Omnichannel
Omnichannel messaging — WhatsApp, SMS and email on one customer record
Send on the cheapest channel that works, fall back automatically when it does not, and see every message a customer received in one timeline — with consent and opt-outs applied across all three.
Why one record beats three tools
Most teams arrive at multiple channels one at a time: email first, WhatsApp when the conversion numbers demanded it, SMS because OTPs need it. Each arrives with its own vendor, its own contact list and its own definition of who has opted out. The result is the customer who unsubscribes from email and keeps getting texts, and the support agent who cannot see what the customer was already told.
The fix is structural rather than a matter of more integrations. When contacts, consent and message history are held once, every rule that matters becomes simple to enforce: a frequency cap counts messages across channels, a quiet-hours rule holds all three, and an opt-out on any channel ends the journey everywhere.
It also changes the economics. WhatsApp is inexpensive for utility messages and expensive for marketing, SMS is the reliable last resort, and email costs almost nothing. A routing rule that starts with the cheapest channel that will reach the customer and only escalates on failure keeps the bill tied to outcomes instead of to how many channels you turned on.
How the channels work together
One contact record
Phone, email, attributes and channel preferences live on one profile, so a segment can target any channel from the same list.
Fallback routing
Name the channels in order and a delivery window; the next channel sends only if the previous one failed or went undelivered.
Consent per channel
Each channel records when and how a customer opted in, and an opt-out on one channel is applied to the others.
Cross-channel frequency caps
Limit messages per customer per day across WhatsApp, SMS and email together, not channel by channel.
One inbox timeline
Agents see every message and reply across channels in one thread, with orders and tickets alongside.
Reports by outcome
Delivered, read and converted per journey, with cost per outcome for each channel it used.
A fallback journey, end to end
- 1
WhatsApp first
Send the approved utility or authentication template — the richest and usually cheapest channel for a customer who has WhatsApp.
- 2
Wait for the event
Watch for a delivery receipt for the window you set, from seconds for an OTP to hours for a reminder.
- 3
SMS if it fails
No delivery in the window, or the number is not on WhatsApp: the DLT-registered SMS goes instead.
- 4
Email for the record
A receipt or long-form copy follows by email, where a link, an invoice or an attachment belongs.
- 5
Stop on reply or opt-out
A reply, a click that completes the goal, or an opt-out on any channel ends the rest of the journey.
A journey, channel by channel
Which channel leads depends on the moment, not on a rule of thumb.
One call, three channels
List the channels in order; sendlz sends on the first and falls back only when it has to.
- POST /v1/messages
- GET /v1/messages/{id}
- POST /v1/webhooks
curl -X POST https://api.sendlz.com/v1/messages \
-H "Authorization: Bearer $SENDLZ_KEY" \
-H "Idempotency-Key: ord_48120_shipped" \
-d to=+919812345678 \
-d route[0]=whatsapp:order_shipped_v3 \
-d route[1]=sms:order_shipped_sms_v2 \
-d route[2]=email:order_shipped_mail \
-d fallback_after=120 \
-d vars[name]=Ananya
{ "id": "msg_01JQ...", "status": "queued",
"route": ["whatsapp", "sms", "email"] }One record, three channels
The controls you would otherwise rebuild in every tool.
- Consent and opt-outs held once and applied everywhere
- One suppression list across WhatsApp, SMS and email
- Frequency caps and quiet hours that count all channels together
- One timeline for agents, one report for the team
Questions on this page
Each answer is written to stand alone, so search engines and AI assistants can quote it.
Will a customer get the same message on all three channels?
No. A journey sends on its first channel and moves to the next only if that one fails or is undelivered past your window, so a customer normally receives one message, not three. Sending on several channels at once is possible, but you choose it explicitly.
Do I need consent for each channel?
Yes, and sendlz records it per channel: when and how the customer opted in to WhatsApp, SMS and email separately. An opt-out on any channel is applied to the others.
Does one template work on every channel?
Each channel needs its own approved content — a Meta-approved WhatsApp template, a DLT-registered SMS template and an email template — but they are grouped under one journey so you build the flow once.
Do I need DLT registration for omnichannel?
Only for the SMS leg. WhatsApp uses Meta’s template review and email uses domain authentication.
Send smarter. Sell faster.
Start free with 1,000 conversations. Bring your own Meta number or apply for a new one — we handle verification, templates and the green tick with you.