Can I extend my Non-Immigrant O Visa in Bangkok and what do I need to bring?

1) : can I do visa extension at CW Bangkok?

-> Yes, if you have TM30 receipt with a Bangkok address and proof of permanent address

2) if yes. How many days of extension will I get? /90 days?

-> Only 1-year extension available is the one based on marriage. You need to meet all the requirements including proof of funds. This 1-year will be added (top-up) to the current stamp.

If you cannot apply for a 1-year extension (for example, not enough seasoning period of your funds), you can apply for 60-day family visit extension. This 60-day could start on the day of application depending on the office.

3) Apart from marriage cert. What else do I need to submit together with extension application?

-> You need to go to CW to get the latest handout of their requirements.

4) Bring wife?

-> Yes, your wife is the reason of your extension and you have to bring that reason to apply for an extension.

5) Anything else that I've missed?

As mentioned, Go to CW to get the latest handout of their requirements. That is the first thing you have to do.

Attached is the general information for 1-year extension based on marriage to a Thai. Detailed requirements of documents vary by the office. you need to get the exact one from the office where you apply for your extension at.