When should I apply for an extension of my Non-O visa based on marriage and having a Thai child?

@Sam ******

you also need a copy of all the pages in your passport (they all will not be needed, but you never know exactly which ones they will want). You need one set of your Thai marriage license documents, there should be two. A copy of your wife's ID card, and a copy of the house book she is registered in. Pictures of both of you in front of where you live, hopefully showing the name, a picture in front of your entry door, showing the room number, or house number, and at least two pictures of both of you inside the apartment. You also need a hand drawn map of how to get there, but some use a Google map, although not all immigration agents accept it. Then you need your two bank letters, one stating it is your account in your name only, and the other showing your deposits, and balances going back three months. Two months is required, but three is better. Then you need copies of your bank book pages, and updated on the day you apply. Make sure you keep copies of everything because the next year you will only need updated bank letters, and new pictures. Oh, and you need a new passport photo for the application. They do scan and keep your photos, so you can not use the same ones next year.

@Dale *********

no

@Dale *********

yes until there decision, which to be honest if you have all the paperwork unlikely they will say no.

@Dale *********

Best go to nearest immigration to you and check all paperwork required. They are not all the same.

Just did mine first time couple of months ago

Mine was

Marriage Certificate.

Wifes ID

Your passport copy all pages

House papers (blue book)

Photo of you and family by house number

Photos of you and family in house.

Copy bank book.

Statement from bank.

This was Samat Sakorn and they are not all the same. Advise you to make extra copies of some so can be used next time.