What are the financial requirements for a Non-Immigrant O visa based on marriage in Thailand?

If your application is done in the uk you are better off showing you uk funds, not only that you could apply for an O A visa if your over 50 which lasts for 2 years. But if your under 50 go for the marriage visa “O”

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IF you are talking about a yearly extension of stay from the immigration office based on marriage there are two ways to meet the proof of funds:

1 - bank 400K baht (or the equivalent) in a thai bank account in your name only for 2 months prior to you applying for your extension.

2 - show proof of 40K baht a month in income either by legally working here with a work permit using tax statements etc OR by using a letter from your consulate stating you get that income from abroad <- that is IF your consulate still issues such a letter (the consulates from the UK, US, Australia & Denmark no longer issue one) OR transfer in to a thai bank account in your name from abroad at least 40K baht per month for the previous 12 months prior to you applying for an extension.

400k for 2 month's before renewal date