Connecting in Narita
 

I posted this also under "Airports" but I'm not sure that board gets the traffic like the destination boards. Appreciate whatever you can tell me.

We are connecting at Narita from Chicago (American Airlines) to Bangkok (Japan Airlines). Will we have to go through immigration or customs at Narita? If not, will we still have access to the American Airlines Admirals Club (we are members) or the Japan Airlines Club (we are flying business class)?

You won't go through immigration or customs, but you will go through a security check after you disembark your flight. You will have access to airport lounges. The lounges are all air side. Just follow the signs for transit passengers.

you might just want to check to see which terminal you land, and what terminal you depart.

i am taking ua to nrt, then ana to sin. ua lands at terminal 1, and ana departs from terminal 2.

I have a question along the same lines, we will be flying into NRT from Dallas on AA and then switching to Thai Air to fly to BKK. After we get off the plane in NRT do we have to go get our luggage and then check them back again into Thai? As you can see this is our first time with a trip this size, thanks for your help!

No, you will check your luggage through to Bangkok. You will not see your luggage in Narita.

This can be confusing, since if you were flying on to another destination in Japan, you'd have to go through customs with your luggage before sending it on to your Japan destination (though it would be checked through to your Japan destination).

When you return to the US, you'll have to go through customs with your luggage at the first location you land in the US, even though your luggage will be checked though to your final destination.

I hope I haven't made it even more confusing by adding this additional explanation!

laurie_ann and travelduo
You both have to change terminals, as your inbound flights from US land at terminal 1 and your connecting flights leave from terminal 2. Just go to Transfer and catch an airside bus to terminal 2. You through-check your luggage to your final destinations. As for accessing lounges, AA AC lounge is located in terminal 1 and as far as I know isn't accessible to arriving pax. You can use JAL's Sakura lounge in terminal 2.