Virtual phone numbers & Verification SMS
Most online services that send verification SMS (a.k.a. One-Time Passwords or OTP)
will not send these verification messages to virtual phone numbers.
Via databases that map phone number prefixes to phone number types, they are able
to detect that the number is virtual and silently block the verification SMS.
As these databases are not perfect, some virtual phone numbers may work for verifying
some online services. However, this should not be relied upon and may change over time
as databases are updated. We have no way of knowing which number prefixes are blocked
by a particular online service at a particular time.
Using virtual phone numbers for verifying online accounts is at your own risk
and we cannot provide support for the online service deciding not to send the
verification SMS to your virtual phone number, as we have no control over whether they
choose to send the SMS or not.
If you need a DTMF.io number that supports verifying online accounts, please use one
of our SIM mobile numbers.
These work just like our virtual mobile numbers for sending and receiving SMS via your
browser, our apps or our API, but they are real mobile phones and can therefore
receive any SMS, including verification SMS.