If I get a "single entry" non immigrant B visa, what exactly does that mean? For example, I want to return to Thailand, and then leave again this week and come back next week. Can I get back in without getting another visa? Have I used up my single entry the minute I leave the country?
TLDR : Answer Summary
A single entry Non-Immigrant B visa allows you to enter Thailand only once for a maximum stay of 90 days. Once you leave the country, you have used up your single entry. To return to Thailand without applying for a new visa, you need to obtain a re-entry permit. There are options for a single re-entry permit (1,000 THB) or a multiple re-entry permit (3,800 THB), which allows you to maintain your admitted stay date upon your return.