How do I apply for a one-year multiple-entry Non-O visa as a US citizen married to a Thai national?

Come in on a 30 days on arrival, after 10 days go and get a non o 90 days based on married to a Thai, paperwork not that bad..... Then change with 1 month left to a 1 year extension based on your marriage. Same paperwork. You report every 90 days to immigration. Paperwork including... At least 6 to 10 photos of you and your wife at home , a up to date paper saying your marriage is still active, up to date bankbook 400 thousand needed, that u must not touch during application.letter from the bank along with the a updated bankbook on the day u apply..... They will visit where u stay and take a couple of photos. I've just been through it all , it's not complicated at all. If u own a house u need the house book , if u rent the lease agreement. Any children of yours need to attend immigration with u when applying.

You will only get a 90 day visa. After you are in Thailand you apply for your one year extension, with lots more documentation. After you complete this and get your extension then you can get a multi-entry re-entry permit.

Are you applying in the States or in country ?

In country you will not get a multiple entry

Long stay departure date...I just say " not yet decided" never had a problem, but always leave before visa expiry date.

I may be wrong and hopefully someone corrects me if I am, but I believe the Non-O from the consulate is only for 90 days. You can get a 1 year extension in Thailand, but not a 1 year visa from the embassy. Only the Non-OA that you get outside the country is 1 year and multi-entry.

This is actually beneficial to you since you will only be required to get 90 days of insurance for your Thailand Pass, and you don't need to show insurance to get an extension inside the country for a Non-O.