im brittish with passport and am going to travel thailand ?

As someone already mention get a tourist visa. It is good for 60 days, then when your 60 days are almost up, go to immigrations and get a 30 day extension for an additional cost of 1,900 baht. Lot cheaper then making all those border runs or flying in and out of the country each time to renew your visa.

You will only be able to stay in Thailand for 30 days if you do not get a visa before you go there. I recommend that you apply for a tourist visa from the Thai embassy or consulate in the UK before you travel. I believe that you can get a double 60 day tourist visa.

The visa rules have just been changed so if you enter by air you will get the 30 days and if you enter via land border crossing you will only be given 15 days.

Get the tourist visa as it makes life much easier.

Cheers, Rick

Best if you get your tourist visa in the UK for 60 days then it can be renewed for a further 30 days at immigration offices in Thailand

I only use the one year non immigrant visa which gives me 90 days every time I fly in. You can download the forms and apply by post. The consul has a good email enquiry line as well if you have any questions