Free "receive SMS online" sites publish phone numbers on a public page, along with every text those numbers receive. The numbers are free because they aren't yours: other people use the same number at the same time, and every incoming message is visible to anyone. With a paid service, a number is set aside for your request for a limited time and only you can see the code.
How free receive-SMS sites work
These sites list the numbers they have. You pick one, enter it on a platform, then refresh the site's page to watch for your message. The message feed is public, so your code shows up right next to someone else's.
Because the same numbers are used by many people over a long period, many platforms recognize them and refuse to send codes. "Temporary 10-minute phone number" services usually work the same way: the number is temporary, but it isn't private.
Comparison
| Free receive-SMS sites | Paid SMS verification service | |
|---|---|---|
| Who uses the number? | Many people at once | Only you, for the duration of the order |
| Who sees the code? | Anyone who opens the page | Only you, in your panel |
| Chance the code arrives | Low; many platforms block these numbers | Varies by service and country; high-success countries can be chosen |
| If no code arrives | No support; you just try again | On Onay360, the order is cancelled automatically and refunded to your balance |
| Cost | Free | A one-time price that depends on service and country |
The real risk of a free number
The biggest risk is losing your account to someone else. When you verify an account with a public number, that number becomes the account's recovery method. Anyone who later uses the same number can request a new login code, and that code will be posted on the same public page.
Researchers have studied this. A study of online SMS receiving services from the University of Padua found that messages sent to public numbers can expose personal information and make it possible to abuse account verification.
Adding personal details, photos or payment information to an account created with a public number makes that risk bigger.
How much does a paid number cost?
With a paid SMS verification service, the price depends on the service you're verifying and the country you choose. For the same service, one country's number can cost several times more than another's. Onay360 has no subscription; you pay only for the number you get, and current prices are on the pricing page without signing up.
When is a free number good enough?
For a throwaway test sign-up with no personal information, one you won't mind losing and won't log in to again, a free number is worth a try. Even then, the code often won't arrive.
For messaging apps, email, social media and any account with payment details, use a number that's reserved for you. On Onay360 you can choose a service and country and get a virtual number whose code only you can see. General risks and precautions are covered in our security guide.