I am flying from Chiang Mai to Europe via Bangkok on Thai. I usually avoid transiting via Bangkok for international flights, so have not made such a trip since well before Covid. I can't remember if I exit Thailand through Immigration in Chiang Mai or in Bangkok, ie. should I check in at the international or domestic terminal at CNX? I know that the procedure has also changed from time to time in the past, so I am looking for recent experience. If you have recent experience, please let me know. Thanks

CM to BKK domestic, the flight and airline abroad is international, so BKK in this case. 
 

Would only be different if the flight was originally starting here but with a scheduled stop over. 

If you're using the same airline to leave CM and then Bangkok, you possibly might be going through Immigration

here in CM; however, more than likely you'll be doing the Immigration exit in Bangkok.  You'll find out for sure 

when you check-in for your flight out of here.

You go to Thai airways international at cnx. They will check your bags thro all the way and give you both boarding cards. You then go up stairs to immagration.  

 

I appreciate all the replies. However, they contain rather different advice. In previous years with similar flights, sometimes I had to go through immigation here, sometimes in Bangkok.  So the question is what is the procedure at present? Has anyone had recent actual experience?

7 minutes ago, neilrob said:

I appreciate all the replies. However, they contain rather different advice. In previous years with similar flights, sometimes I had to go through immigation here, sometimes in Bangkok.  So the question is what is the procedure at present? Has anyone had recent actual experience?

Why don’t you call Thai Airlines?

In May I went to Australia and return from CNX, you will clear immigration here in CNX and will get the C.I.Q sticker applied to your shirt, so you stay in international all the way to your destination. As mentioned before you will get both boarding passes here in CNX.

 

I'm pretty sure all the Thai Airways marketed flights from CNX are operated by Thai Smile, so you'll be looking for their check-in desks.

 

As of last week, when you got to the desk shown on the screens, those with domestic destinations were being re-directed to another totally different desk group.  I followed that route so cannot answer with certainty about immigration.

You definitely check in at International, get both boarding passes and bags are checked through. You get a CIQ sticker and when getting off in Bangkok the staff direct you through a transit section 

 

The BKK airport website has details.

I remember this CIQ "side exit" when walking to baggage claim after leaving a domestic flight. It's hard to overlook.

Thank you very much to Kuzie57 and DFPhuket for their valuable information

I travel from CNX to Europe via BKK at least once a year (twice in the last months, last time in April).  Only ONCE in 2020 (height of Covid) did I have to check in twice - get my bags from the domestic flight then high-tail it over to the int'l flight, then gop through passport control in BKK. Major pain and good job I had several hours to do it.  This has been the case for at least the last ten years or more.

 

Usually I fly Thai and sometimes they say check in at the domestic desk, last two times it has been the International one (smaller queue! ???? ) Doesn't seem to be any logic to it. The end result is the same: bags checked in all the way, and boarding passes for BOTH flights. Get my CIQ sticker and go through passport control in CNX (again much MUCH smaller queue!)