move watch line number to iPhone

This answer doesn’t make sense. The Apple Watch phone number is t a placeholder, it is a number on a cellular watch plan. I have the same question as the origins poster. 

My son has a watch w a cellular plan and phone number. He’s been using it as part of our family plan for 1-2 years. Now he got an iPhone SE (3rd gen) which comes w a new phone cellular plan/line (still in our family plan) but he wants to keep his old number and deactivate the watch. 

Nobody seems to know how to do this - is it really not possible? He is not planning on using the cellular plan on the watch any more so we can factory reset it or do whatever is necessary with the watch - and sync it to his new phone later (w the old number in tact). How do we do this? 

I'm in the same boat, I got my daughter an apple watch at 10, now at 13 I tried to upgrade to an iPhone and keep her number.  I was told that's not possible.  I thought this was ridiculous AF.  All relatives and friends have her number current number and nobody like changing number for stupid reasons.

To move your apple watch number to a phone you have to transfer the number to a different provider, and you have a switchback period of 59 days.  I got the apple watch unlocked from ATT and transfer the watch to T-mobile at $10 a month.  When the switch back is over, I switch back to the new ATT phone. 

I still can't believe ATT does not allow to upgrade standalone apple to an iPhone.  

Now that I know what I know, I may just get my other daughter and son apple watch on T-Mobile, and switch when they turn 13. 

…And keep the number that was on the watch line?  I spent 3 days, several calls to tech support, and 3 corporate stores, including 1 T-mobile store.  It’s NOT possible to upgrade a watch line to a phone line and KEEP your watch line number. The problem is not changing the watch line to a phone, the problem is you cannot keep your watch number.

And keep the number that was on the watch line?  I spent 3 days, several calls to tech support, and 3 corporate stores, including 1 T-mobile store.  It’sNOTpossible to upgrade a watch line to a phone line and KEEPyour watch line number. The problem is not changing the watch line to a phone, the problem is you cannot keep your watch number.

Maybe there is something we are not aware of?  🤔  The number assigned to watches and tablets is usually assigned just for data purposes. Watches are designed just to be a companion device to a phone number, not a phone number itself.   The only thing I can imagine that is the cause of this problem is that they are unable to use that number which has been designated as data only as a voice line?  And yes I'm just musing and spitballing possibilities here.

It's possible that's true. It's also possible they just don't know what they're doing.  

Just for the heck of it,  file a better business bureau complaint online. The complaint is forwarded to AT&T upper Management and someone will contact you. If they say that that's the case that that particular number can only be used as a data number not a voice line, then I will believe it.  (Although the fact that another service provider won't allow it as a voice line does carry some weight). ☹️

I do know I have canceled a voice/phone line and had it converted into a tablet line. But it has the same area code as all of my other phone numbers.  Converting it back to being a voice line would not be an issue

Yes, there is something YOU are not aware of, not "we".  It's obvious you still do not understand the issue, after it was stated by the ATT help at the beginning of this thread and from commented accounts of the issue.

1) The Apple watch was a standalone,  it's not associated with an iPhone

2) The Apple watch was for a minor which was paired with a parents phone

3) The Apple had data, text, and voice service, same as a phone.  You can call and text the apple watch via its number.

4) Was told ATT does NOT have a path to upgrade a watch line to a phone line and  KEEP the number that was on the watch, this is the issue.  Do you change your number when you change phones? The watch was used like a phone in its very basic usage.

5) The only solution is to move the line to another carrier, I used T-Mobile, wait for a "switchback" period of 59 days, then transfer number back to ATT to the phone line

I hope this is plain enough for you to understand, you cannot upgrade a watch line to a phone and keep the phone number with ATT.  I asked T-Mobile if this was possible, and they said "yes", but have not been verified.  

🤦🏼‍♀️

You have re-explained exactly as you did in your original post and I understood it the first time.   😑

I am granting that you and I do not work for a cellular provider therefore *we*...   

*We* do not understand all of the technical aspects of cellular services.  And *we* do not understand why this particular watch number cannot now be used on a phone.   

    So *we* cannot understand why...

several calls to tech support, and 3 corporate stores, including 1 T-mobile store.  It’s NOT possible to upgrade a watch line to a phone line and KEEP your watch line number. 

And  I postulated that the number that had been assigned to the watch is incompatible as a voice number for a phone, despite essentially having been used in that manner on the standalone watch.

Then ...

As suggested file a better business bureau complaint online. (The complaint doesn't do anything other than forward to AT&T upper Management where someone will contact you and directly address your question and problem).  At least you will get a more detailed reason why they cannot allow the phone number associated with your standalone watch used for voice calls to be turned into a voice line for a phone

Or maybe they can get around it for you so you don't have to transfer back and forth to T-Mobile. We're at best you can say you got conflicting information because one person said no and someone else said yes.

I called AT&T support and they were able to put the number from a cellular Apple Watch onto an iPhone. They took the number from the watch eSIM and put it into the iPhone eSIM. 
After that action the iPhone works as expected and the watch can be paired via Bluetooth with that iPhone. I’m likely going to get the watch set up with a new number for a younger kid 🙂.
This thread educated me about what to say so I thought I’d pass this successful case on. 
I hope that helps some people!