Key Takeaways
- WhatsApp opt-in rules and SMS STOP/opt-out are different legal and product regimes — do not conflate them because a search says “WhatsApp SMS gateway.”
- WhatsApp Business API needs template/opt-in rules on Meta’s network. Android SIM SMS needs consent + STOP handling on the GSM path.
- We are not a WhatsApp BSP. Our product is Android SIM SMS/MMS.
- Honor STOP on SMS promo lanes; never auto-reply STOP keywords into OTP threads.
- You bring the phone and operator airtime. We meter devices and send volume.
Opt-in is not STOP — and not the same channel
WhatsApp SMS gateway searches explained — opt-in rules contrast: people paste “WhatsApp SMS” into Google and merge Meta Cloud opt-in with GSM STOP keywords. Hub: WhatsApp SMS gateway. OTP channel pick: OTP on SMS vs WhatsApp. SMS STOP product: auto-reply and STOP.
A WhatsApp opt-in checkbox does not unsubscribe an MSISDN from your SMS promo queue — and STOP on SMS does not close a WhatsApp thread.
WhatsApp opt-in vs SMS STOP
| Topic | WhatsApp Business API | Android SIM SMS |
|---|---|---|
| Entry | User opts in to WA business messaging | Consent for SMS (law + your policy) |
| Exit | WA opt-out / block / template rules | STOP/UNSUBSCRIBE → suppress table |
| Network | Meta / BSP | Operator via your SIM |
| Our product | Not this | Yes — devices + volume fee |
What the search mixes up
“WhatsApp gateway” may mean BSP automation; “SMS gateway WhatsApp” may mean SMS fallback. Disambiguate before you write one suppress list for both. WA vs Android depth: WhatsApp Business API vs Android. This is not legal advice — counsel owns PECR/TCPA and local rules.
Ops checklist by channel
SMS: persist STOP, exclude OTP devices from auto-reply, verify inbound while the phone is online. WhatsApp: follow template and opt-in docs on WhatsApp Business Platform. Live SMS API: Developer Center.
Cost
SMS: devices + send volume + your operator airtime. WhatsApp: Meta/BSP conversation pricing. Separate ledgers. Free on our platform: 1 device / 300 SMS lifetime. Starter, Professional, and Business list Unlimited SMS as platform send volume; that is not unmetered carrier SMS.
Checklist
- Separate WA opt-in store from SMS suppress table.
- STOP never fires courtesy SMS on OTP SIMs.
- No Meta Cloud ↔ SIM conflation in runbooks.
- We are not a WhatsApp product.
- Counsel reviewed for your markets.
Next steps
pricing, SMS STOP how-to, acceptable use.
Related product pages
Jump to the live product docs for this topic—not another long-form article.
- device and SMS volume pricingPlans and allowances
- Twilio vs Android SMS gatewayCloud vs own-SIM cost model
- Android SMS gateway product guideDefinition, product, and how to buy
- SMS API documentationLive endpoint reference
