What are the requirements for obtaining a volunteer visa in Thailand, and do you need a work permit for long-term volunteering?

As far as I know when I enquired you still need a work permit to volunteer. The easiest way is to get an organization to sponsor you,

You can look at the avi website they do a lot of volunteer work in Asia

@Cheryl ***********

I would still make the trip to the immigration office, or better yet, have the place you're going to volunteer at call them and ask if you can change the reason for your extension from dependent to volunteer inside the country.

You're not changing ANY visa, only the reason for your extension.

I would imagine you cannot do it in country and you would first go cancel your extension based on being a dependent of someone's extension, then take the documentation from where ever it is that you're going to volunteer and go to a thai consulate in another country and buy a 90 day Non-O visa.

I say that because I have personally never ever heard of it being done. I'd say take a trip to your local immigration office to be sure (and report back on what they say if you would)

I have no idea, so I ask our most knowledgeable source:

@Tod ********