Not free for meaningful numbers of requests, but I've used APIs like numverify[1] to do this before. There are probably per-carrier APIs you can request access to.
Not the most scientific approach, but you could send a message to every provider using the same number. If you get a "message not received" bounce back, then that's a good indication of which carriers are not the correct carrier.
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So, how do you lookup a phone number's provider for free?
Not free for meaningful numbers of requests, but I've used APIs like numverify[1] to do this before. There are probably per-carrier APIs you can request access to.
[1]: https://numverify.com/
Not the most scientific approach, but you could send a message to every provider using the same number. If you get a "message not received" bounce back, then that's a good indication of which carriers are not the correct carrier.
That was what I came to checkout the code for, thinking they put some cool logic in there.