Universal SMS OTP
SMS OTP verification is the baseline every phone can receive. There is no app to install, no account to hold and no network beyond the mobile one, which makes it the channel to reach a user you know nothing about yet. It is the widest reach of the four and the only one priced per country, because operator cost is what sets the price.
You never name a channel on a send: routing picks it from the recipient and your channel order. See Channels & routing for how that decision is made.
When to Use SMS OTP
Where it fits
- Works on any handset, including feature phones with no data connection
- No prior relationship needed: nothing to install, nothing to opt into
- Best first channel when you cannot tell what apps a user has
Worth knowing
- The only channel whose price varies by destination, from a fraction of a cent to several cents
- Delivery depends on the operator that accepts the message, so rates are a floor rather than a quote
SMS OTP Pricing
Priced per country, because operator cost is. Rates run from $0.0008 to $0.4238 per verification across 199 countries; United States is $0.0132. Each figure is the cheapest route we can deliver on for that country, so treat it as your starting point.
Compare every channel and country, and estimate a monthly cost, on the pricing page.
SMS OTP in the Docs
The reference behind this page, for when you are ready to integrate.
The Other Channels
The same two API calls cover all four, so you can put more than one in your order and let routing pick.
Ship verification
with one prompt.
$3 free credits. No credit card. No sales call.
Your first OTP in 10 minutes.
