Originally Posted by
jiejie
Yes, and to clarify further if this is your situation, there is a separate immigration area for connecting/transfer passengers to HKT, CNX, USM, and a couple of other places...so look for the signs once you get into the terminal airside and don't go for the main normal BKK immigration queues.
Yup, and to further elaborate on this, you'll clear immigration at the confluence of A,B and C concourses.
The domestic destinations that have customs are: HKT, CNX, CEI, USM, KBV and HDY. All other domestic connections require bags to be picked up in BKK and re-checked in on the fourth floor.