WhatsApp or SMS for business messaging?
PingPlug · Updated
SMS reaches any working mobile number and needs no app, but sending to US numbers requires carrier registration and is billed per message. WhatsApp reaches only people who use WhatsApp, needs no carrier registration, and requires a Meta-approved template to open a conversation outside a 24-hour reply window. Which is better depends on whether your customers use WhatsApp, not on which channel performs better in the abstract.
Reach is the first and largest difference
SMS assumes only a working mobile number. That is its real advantage and it is a big one.
WhatsApp assumes the recipient has the app and uses it. Where that holds it is a rich channel; where it does not, the message cannot be delivered at all.
No feature comparison outranks this. Check your own list before comparing anything else.
Getting permission to send
SMS to US numbers goes through carrier registration — a brand and a campaign, vetted before traffic flows.
WhatsApp goes through Meta: each business-initiated message must match a template Meta approved, in a category Meta assigned.
Both are gates. One is a registration you complete; the other is a review you return to whenever the message changes.
The reply window
SMS has no equivalent concept. You may send whenever you are permitted to.
WhatsApp opens a 24-hour window each time the customer messages you, inside which you can reply freely. Outside it, only a template will send.
This shapes how conversations are designed more than most feature lists suggest.
What each one carries
SMS carries text and a link, with tight length limits before it splits into several billed parts.
WhatsApp carries images, documents, buttons and structured replies, and keeps the history in one thread.
If what you send is a six-word appointment reminder, that richness is not a reason to change channel.
Cost works differently, and both change
SMS is generally priced per message, plus registration and carrier fees.
WhatsApp prices conversations rather than individual messages, and Meta has revised that model more than once.
Any specific rate on a vendor page ages badly. Take the numbers from the carrier and from Meta directly, on the day you decide.
Where opt-out sits
Both channels expect a stop request to be honoured, and both punish businesses that ignore one — carriers through filtering, Meta through the quality rating on the number.
Whatever tool you use, the question worth asking is whether a stop is recorded once against the person and respected everywhere afterwards, or handled per campaign.
PingPlug is WhatsApp-first and does not send SMS, so it is only the right answer if WhatsApp is where your customers already are. It records an opt-out against the contact and applies it to later sends rather than per campaign, which is the part of the comparison above it can actually speak to.