SMS coverage

Axowl sends phone verification codes by SMS to 76 countries. The same list applies to every place a code goes out by SMS:

organization phone OTP — POST /api/org/otp/send and the public contact OTP;
end-user MFA for your app’s users — POST /apps/{key}/auth/mfa/enroll/send, the code sent with a login that returns mode: "challenge", and POST /apps/{key}/auth/mfa/challenge/resend.

A number in a country outside the list is not sent to and costs nothing. The request fails with region_not_supported, so you can show the user another way in (passkey, email, or a sealed device) instead of a code screen that never fills.

Korean numbers on an app group with a linked KakaoTalk channel get the code as AlimTalk first; see KakaoTalk AlimTalk. The country list below decides the SMS path.

Codes are delivered as text messages only, including to U.S. and Canadian numbers. There is no voice-call delivery. Texts other than codes (approval confirmation links) go only to numbers whose owner opted in to SMS, and texts to +1 numbers end with “Reply STOP to opt out.” On end-user MFA, channel (and smsChannel on a login) is "sms" or "alimtalk".

Country groups

Countries are in three groups. The group sets how many codes one phone number can receive in 24 hours. Only codes that were actually delivered count toward the limit — a failed send does not use up an attempt.

Group	Codes per number per 24 h	Countries
Standard	No daily cap (normal resend throttling only)	44
Limited	2	18
Restricted	1	14

Limited and Restricted countries are the ones where SMS toll fraud (artificially inflated traffic) is common. They also share a platform-wide daily safety limit; ordinary sign-up traffic does not reach it.

Standard — 44 countries

Region	Countries
North America	United States (including Puerto Rico and the U.S. Virgin Islands), Canada, Guam
Asia-Pacific	South Korea, Japan, Taiwan, Hong Kong, Singapore, Australia, New Zealand
Western Europe	United Kingdom, Ireland, France, Germany, Netherlands, Belgium, Luxembourg, Switzerland, Austria, Liechtenstein
Southern Europe	Spain, Portugal, Italy, Greece, Malta, Cyprus, Gibraltar
Nordics	Denmark, Sweden, Norway, Finland, Iceland
Central and Eastern Europe	Poland, Czech Republic, Slovakia, Slovenia, Croatia, Hungary, Romania, Bulgaria, Estonia, Latvia, Lithuania
Middle East	Israel

Limited — 18 countries (2 codes per number per day)

Region	Countries
Latin America	Mexico, Brazil, Argentina, Chile, Peru
Asia	India, Indonesia, Malaysia, Thailand, Philippines, Vietnam
Middle East	United Arab Emirates, Saudi Arabia, Qatar, Kuwait, Turkey
Africa	South Africa, Kenya

Restricted — 14 countries (1 code per number per day)

Region	Countries
South Asia	Pakistan, Bangladesh, Nepal, Sri Lanka
Southeast Asia	Myanmar
Central Asia and Caucasus	Uzbekistan, Kyrgyzstan, Kazakhstan, Azerbaijan
Europe	Russia
Oceania	Fiji
Africa	Nigeria, Ghana, Tanzania

+1 numbers outside the United States and Canada

+1 is shared by several countries. Caribbean and Atlantic area codes — for example Jamaica (+1 876), the Dominican Republic (+1 809 / 829 / 849), the Bahamas (+1 242) and Bermuda (+1 441) — are not in the list and fail with region_not_supported. Puerto Rico, the U.S. Virgin Islands and Guam are covered.

Errors

Where	Response	Meaning
Organization OTP	`region_not_supported`	The country is not in the list. Nothing was sent.
Organization OTP	`region_daily_limit`	This number has had its daily codes for a Limited or Restricted country. Try again after 24 hours.
Organization OTP	`region_fuse`	The shared daily safety limit for Limited and Restricted countries is reached. Try again later.
End-user MFA	`502 { error: "region_not_supported" }`	Any of the three cases above. On a login, `smsDelivered` is `false` and `smsError` is `"region_not_supported"`.

Phone numbers must be in E.164 form (+ and country code). A number without a leading + is treated as outside the list.