Email to iMessage Phone Number

I need to send an OTP authorization code to verify a user's phone number. For testing, I've been using an e-mail sent to a phone number via AT&T's gateway but I don't want this app to be limited to AT&T customers only so I'm looking for a better solution.

It occurred to me that perhaps I could use iMessage for this instead, as long as the user has their phone number setup in their iMessage account. The question is, is there an e-mail address I could send to like I do with AT&T such as 5551234567 @ imessage.com?

I do not want iMessage to open on the user's device. That would defeat the entire purpose. I am trying to figure out a way to send an e-mail to user's phone number that is already setup in iMessage on their device/account.

iMessage doesn't have any functionality like many carriers' SMS-email functionality, so unfortunately this would not be possible.

There are many widely-used services that can send SMS to phone numbers regardless of the carrier that might be of use!

I've been looking at those 3rd party services, but since we only need to do this in order to verify a phone number added to a user's account, I haven't found any that don't have monthly minimum charges, and really good rates. Any chance you could recommend a few to look at?

Also, perhaps instead of looking at it as I am now, there is a better solution for verifying a phone number (i.e. user enters a phone number and we send them an OTP verification code)?

Email to iMessage Phone Number
 
 
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