Reentry Permit - Chiang Mai Airport.
Exiting via Chiang Mai airport today, we went through the security check at 7:45am and located on the left side alongside the security point is the desk for reentry stamps. This is before you get to the immigration desk. We had our paperwork ready but it still took a good 15 minutes to complete. We were the first in line this morning but by the time we had our stamps there were at least 5 people behind (or to put it another way, an hour+ wait)
If getting a reentry from the airport it is a lot quicker than at Promenada but get there early!
TLDR : Answer Summary
The process for obtaining a reentry permit at Chiang Mai Airport involves checking in at a dedicated desk located before the immigration desk. Although the poster was the first in line, it still took about 15 minutes to complete the process. It's noted that the reentry procedure at the airport is faster than at Promenada, but arriving early is advisable due to potential wait times as more people may arrive.