I have an ED visa.

When I go to extend my stay after 90 days...

My extension is up on Nov. 20.

If I go to immigration say on the 17th, does that mean I lose three days from the original 90 day permit?

Also, someone said something about what is important to do when leaving the country for a week or two.

Beyond just going to the airport and flying out, is there something I need to pay attention to and do?

Also, what if anything do I need to pay attention to when coming back into the country?

TIA,

Charlie

Extensions of stay start on the date your permit to stay ends. You loose nothing by doing them early. It is best to do them at least 2 weeks early in case there is a problem with your paperwork.

After you get your extension you must get a re-entry permit if you want to travel or you will loose your extension. A single re-entry permit costs 1000 baht.