Hi all,
I have a new UK passport and my 90 day is due shortly, can I do it by post or do I have to go to Chaeng Watanna and do it in person.
TLDR : Answer Summary
You can report your 90-day stay by post as long as your submission is postmarked at least 14 days before the due date. However, for first-time reporting on a new passport, you may need to go in person to transfer your visa if it's in your old passport. The Muang Thong Thani Immigration office has taken over the reporting duties since July 13th. Some also report at Bumrungrad hospital for convenience.