I am married to a Thai national, have been for some time. I am also too young for the Non-O based on Retirement, so being married allows for an extended time in the Kingdom to annoy my loving wife.
Applying for a commonly named marriage visa, which in reality is a Non-Immigrant O based on the condition of marriage can be a headache. There are two real options available. The simplest explanation is that with both options you obtain the visa from a Thai Embassy outside of Thailand, then come back into the Kingdom. Option one gets you a three month visa, and then you apply to have permission to stay extended for 12 months. There are many requirements for this, outlined in the video.
Option two, is a visa that is a multi entry, valid for 12 months, less conditions but the downside to it is you only get stamped into the Kingdom for 90 days at a time.
Be aware! Check current information regarding obtaining a visa, check the Thai Immigration website AND also check the Thai Embassy website for the country you are applying in.
How to for a Non-O Marriage Visa for Thailand
How to for a Non-O Retirement Visa for Thailand
How to for a Non-O Child Visa for Thailand
[embedyt] https://www.youtube.com/watch?v=t-IvHNkBnrY[/embedyt]