If you apply for a retirement visa outside of Thailand you are given a Non-OA visa. The Non-OA visa requires you to have health insurance, which is very expensive to buy inside Thailand. You can find the notice of this requirement and a list of acceptable Thai insurance companies here: https://longstay.tgia.org/home/companiesoa If you don't have the insurance from a company in the USA which will cover you for as long as you are in Thailand then don't apply for a visa in the USA. If you have health and accident insurance from a company in the USA which will cover you for as long as you are in Thailand you can apply for a Thai retirement visa while you are in the USA, but I don't recommend doing so. Wait until you enter on a 30 day visa free entry then a couple of days later go to immigration and apply for a retirement visa. Retirement visas issued in Thailand are Non-O visas, which do not have the odious health coverage requirement. You won't be issued the new visa before the 30 days runs out but you will be allowed to pay 1900 Bt for a 30 day extension to give Thai Immigration long enough to consider whether or not to give you the visa. You will be issued the new Non-O retirement visa just before the extension runs out. The only potential problem is the requirement for you having 800,000 Bt untouched in a Thai bank account for 2 months before the visa is issued and 3 months after. If you already have this then it isn't a problem. If not you may have to get a 60 day extension (or two 30 day extensions) before the visa is issued. The next year if you renew your Non-O visa you will have to have the untouched 800, 000 Bt in the bank 3 months before and 3 months after the visa is renewed.