Carrier Bought AT&T XS, intending to use T-Mobile SIM.. how to activate?

[Virgo]

I bought an AT&T iPhone XS (paid in full) from Best Buy, will pick up on Friday. Reason is because I wanted to pay with a gift card, and BB does not sell T-Mo models for some reason.

Question is should I activate it with the AT&T SIM first, or should I plug in my T-Mobile SIM right away? Is there any unlocking process I need to do?

Thanks in advance.

 

[ShinyApps]

Put the TMO sim in first.

 

[ray737]

Just put in the TMO sim.

 

[awdods]

Did you actually sign up for AT&T? If so, you may have to request a carrier unlock. Shouldn’t be a problem since you paid in full. Just google how to request it.

Once request goes in AT&T will say it can take several days to process but I’ve never had it take longer that an hour or two.

 

[Virgo]

Did you actually sign up for AT&T? If so, you may have to request a carrier unlock. Shouldn’t be a problem since you paid in full. Just google how to request it.

Once request goes in AT&T will say it can take several days to process but I’ve never had it take longer that an hour or two.

Yes I did, that's what I was wondering because I stumbled upon something like that while googling. So in that case should I leave the AT&T SIM inside before sending the request?

 

[awdods]

I don’t think so.

They just ask for account info and IEMI. After request is approved their instruction state to either a) Backup and do a full restore if you’re still using an AT&T SIM or b) Insert a new SIM if you’re using a non-AT&T SIM.

Obviously b is what applies to you. Easy!

 

[Virgo]

I don’t think so.

They just ask for account info and IEMI. After request is approved their instruction state to either a) Backup and do a full restore if you’re still using an AT&T SIM or b) Insert a new SIM if you’re using a non-AT&T SIM.

Obviously b is what applies to you. Easy!

Thanks I’ll try! Can’t wait for Friday!