Can I apply for an in-country Non-O visa based on marriage with a short rental agreement?

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For requirements for an initial in-country Non-O visa based on being married to a Thai, you can refer to this to get a rough idea as general information.

/6.FOR-PROVIDING-SUPPORT-TO-OR-BEING-A-DEPENDANT-OF-A-THAI-CITIZEN-SPOUSE-VISA-NON-O.pdf

@Andy ********

IF you're married to your child's mother you are highly unlikely to get a Non-O visa or a yearly extension issued in country based on being the father of a half thai child.

They usually make people married to thaiz get the visa/extension based on marriage not on having a half thai children.

Sadly, I'm pretty sure the answers are not what you're wanting but

For # 1 - you and your thai wife need to slog on over to the Jomtien Immigration office and ask them IF you can apply for the 90 day Non-O visa based on marriage with just a 3 month lease

AND

For #2 - once you get to where ever it is you're moving to, you need to slog on over to that immigration office and ask them if you can do it. In THEORY, you should be able to IF you file a TM30 showing you now live up north in the area served by the immigration office up there BUT that Jomtien stamp is often times a "stamp of death" <- because of the back door, agent gotten visas/extensions from that offce. AND people who have gotten their initial visas from there did run into a LOT of issues trying to get their yearly extension granted after they moved to another province.

I would almost say, WAIT until you move, then do the process up there if they can do it

OR

something that might be easier and less worrisome would be; go the thai consulate in Savannakhet and get a single entry 90 day Non-O visa based on marriage, enter get stamped in for 90 days and then apply for the year at your immigration office up north.

I say do that because you won't have any issues getting a yearly extension from a Non-O from Savannakhet at ANY immigration office as long as you meet the requirements

AND

Savannakhet is a "soft touch" consulate that requires minimal documentation to issue that visa and does it in 2 working days total with walk up service (no appointment needed)

You will be applying for an Extension of Stay based on marriage not a visa.