How long will US to UK shipping take?

So I ordered an iPhone 6 from TMobile USA for reasons I won't delve into. It's being shipped by FedEx so how long will delivery take, it's estimated to take a week but that's an estimate, is it about accurate?

Oh that's easy!

At best it will take 5 days on standard-first class shipping.
At worst it will take up to 20 days.

On average it takes 7-10 working days for parcels to arrive. Basically, the more the item is worth the longer customs will hold it for, this can take over a month. You will also be required to pay a fee on it as it is worth more than £15, it can take some time to process.

Things I've had on a basic postal rate from the US have taken me 11 days to arrive.

I didn't know they ship outside US. Anyways, shipping depends on what you've selected during checkout. It might take anything from 3 days to 10 days. More info would've been usable. Also, T-Mobile US iPhone 6 won't work with T_Mobile UK and you'll need to get the phone factory unlocked. If you need more info, feel free to mail me.