Unlocked Xperia Z3 Compact on AT&T?

[RoscoV3]

I would like to know if the unlocked version will be compatible with AT&T.  I know it is on T-Mobile and that their networks are sort of compatible but I want to make sure I'm not going to be buying something that isn't 100% functional on the AT&T network. 

Thanks all

[JohnD1]

It worked "right out of the box" for me - including LTE.

Hope this helps,

John

[lettucefish]

First off thank you for the reply, as dealing with ATT in my part of the world is worse than a root canal with out pain killers, that said, what kind of visual indications do you recieve that lets you know that you are recieving LTE service

[JohnD1]

Indeed - it is my pleasure!

Sorry to hear about your local AT&T store! By comparision - my local store has been tremendous.  I've been a customer since 2007 (first version of the iPhone) and they've been a terrific resource. I'm very biased, however - as they got my one of my iPhones set-up remotely (I was in Haiti during that time) during the earthquake - and post earthquake for rescue and recovery. All calls were free, as was all data - which really assisted while coordinating rescue efforts. Returning to the US was quite impossible - so my local store did it for me remotely...

Anyway - my Z3C came in from HK just after the Sony release overseas. The firmware is a bit different then those imported from the UK, as I understand? Therefore, mine showed "LTE" immediately as opposed to what the UK phones show (only "H+", even on LTE). As well - mine immediately showed  H or H+ or LTE depending on the connection. And doing a Spedtest - when running on LTE, had the same throughput as my wife's iPhone 5S on LTE - so, indeed - it was at LTE bandwidth/speed.

Hope this helps and my best always!

- John 

[lettucefish]

Thank you

[sparker561]

The above detailed instructions for what to enter worked immediately for me, and that is with using an att micro sim I cut down to a nano.

[sparker561]

 I have an unlocked Z3 C and brokeman's instruction on what to enter worked well for me.

[Tone314]

Maybe you don't have the right sub model.. you need D5803.  This one is optimal for use in the US.