What is the best visa strategy for a US citizen married to a Thai national while waiting to register their marriage in Thailand?

Ive done the same as you up to the border run 45 days left end of April came back three weeks ago and was pulled aside and told to get a retirement visa.

Be sure to get your US marriage certificate certified before she leaves the US. The process takes 2-3 months and is kind of a pain. General process is:

Get a certified copy at the county office where you were married.

Have it certified by the state.

Send it to the state department (in Washington DC) for certification.

Send it to the Thai Embassy (in Washington DC) for certification.

Then, in Thailand, you need to have the document and your passport translated and then certified by the ministry of foreign affairs. This will require a trip to the US embassy to have your passport authenticated before it can be translated and certified... The US embassy will also provide certification of your passport via post. You need to check the embassy website for those details.

Then, you can go to the local amphur to have your wife register for a change of status. Then, you can begin the visa process.

There is a process to do this in Thailand, but it sounded more convoluted, and kind of like the exact same process, but just from here. Anyways, current processing times for the US part of this can vary depending on how quickly you can turnaround the document between certifications. Thai time frame depends on how quickly you can get in to the US Embassy for a certification of your passport. I used an agency that specializes in visas and passports in the US and a translation service in Thailand... Spent about 600 USD total including all shipping and charges from the respective agencies/embassies.

Heads up, all your read about the simplicity of getting married no longer applies. It’s now agent only, or takes 2-3 months if you DIY.

If for whatever reason you don't want to head back to the States, December is a LONG time to continue visa and border running in Thailand on tourist visas given yr already extensive history.

I'd suggest leaving for Lao or Cambodia, spending 2 or 3 months there (perhaps make yourself look more like a tourist by popping into Vietnam as well) THEN meet your wife in Savannakhet or Ho Chi Minh City in December to apply for a marriage visa (I think they'll issue one even if your marriage is registered in the USA).

Alternatively, apply for a tourist visa in Vientiane OR Savannakhet OR Phnom Penh in late November to give you enough time to do the marriage visa conversion in Thailand (after you register the marriage inside the country).

I'd suggest spending some time with your wife in America, then coming back to Thailand together with a non-O marriage visa, obtained using your USA marriage license. If you can't get a 12 month one, go for the 90 days then extend in Thailand.

I would be more worried about messing things up for her in America.

Maybe get another one from Lao

Even with a tourist visa you still run the risk of getting pulled out of line at the airport and interrogated about why you're spending so much time in Thailand without a proper long term visa. It's no guarantee that you'll be allowed into the country.

You might also want to check the destinations you listed for example you can't get a tourist visa to Thailand from Bali as the Thai embassy there no longer serves foreigners, you can only apply at Jakarta. Other countries like Japan may only allow those with residency in Japan to use the embassy to apply for a visa.