What SMS verification costs: OTP vs permanent

A per-activation OTP number costs a small amount each time you need a code. A permanent number costs a flat monthly or yearly price and receives unlimited SMS while you renew.

Which is cheaper depends on how many codes you need and how long the account lives.

Divide the monthly price of a permanent number by the per-code price of an OTP number. If you need more codes than that per month for the same account, the flat plan costs less. If you need fewer, per-code wins.

Prices differ by country and service, so use the live numbers rather than a rule of thumb. Our calculator does the arithmetic with current catalog prices.

An OTP number cannot be reused, so an account that later asks for another code means buying again, and the account may be unrecoverable if the code goes elsewhere. A permanent number costs more upfront but avoids that risk.

Also consider crypto network fees, and whether refunds apply if a code never arrives.

One-off registration you will never revisit: OTP. Anything with two-factor authentication, recovery or repeat sign-ins: permanent. Use the calculator to confirm for your numbers.

Suppose an OTP number costs a few cents per code and a permanent number costs a few dollars a month. If you expect fewer codes than the monthly price divided by the per-code price, OTP is cheaper; above that, the flat plan wins.

Real prices vary, so plug your own figures into the calculator rather than relying on this example.

The cheapest option can be the most expensive if the account is lost. Recovering a locked account can take days and sometimes fails, which is why cost should be weighed together with how important the account is.