Yes that is enough time. Yes there is lots of English signage at NRT.

Aloha!

its plenty of time.. some of it will be spent clearing security... narita makes transit passengers go thru a clearance yet again with their carry on luggage.. it usually takes quite a while..

when checking in in usa just check your luggage thru to bkk--that is normal.

and in bkk look at tv monitors to see which carousel your flt's luggage is on--tv after immigration.

I sure hope three hours is enough because United is only giving us 2 hours connecting from Chicago.

I fly thru NRT all the time, on my way to BKK. It is plenty of time. You do not have to reclaim your luggage. After you deplane, you will get into a (sometimes long) line to have your carry-on bags screened and your passport and boarding pass checked. Then just go down the escalator and you will find the United Lounge (if you are a member or have access with your ticket) and plenty of shops to check out. That always helps pass the time.

Thanks, Carol. When are you flying to Bangkok again?

Narita is very efficient, and also hectic. There are a couple of areas designed in the Asian way to promote a quiet interlude of rest. One other tip: Some restaurants and stores will accept US currency for small items.