Living in Thailand can be fun, rewarding and relaxing in a stress free life once you know the visa requirements and get settled in. The following are the easiest long term visas to obtain. We will not discuss the employment visa as it is very involved in paperwork and impossible to obtain unless you are employed by a company here in Thailand in which case they will file the necessary paperwork for you that is required from their company or you should consult a lawyer.

All long term visas require a Non-Immigrant visa in your passport. Non-Immigrant Visas are obtainable from the Thai Embassy in your country for the purpose of investment, visiting family, and a job at a company in Thailand. It seems that the Thai Embassy will not issue them if you have not been to Thailand before so you should get a "Tourist Visa" for your first visit which allows you 60 days and can be extended another 30 days at any Immigration Office. If any of the following listed items are done while you are in Thailand, then the Immigration Office in Bangkok can change your visa to a Non-Immigrant Visa which can then be extended for indefinite 1 year periods.  This is the way most all foreigners live in Thailand although I have met several who go to the boarder every 30 days to get their passport stamped. Too much of a headache for most people, but that is legal and I have heard of one person living here for 17 years so far that way.
You will find detailed information below along with a link to the Thai Embassy's web site in the USA  and the Immigration Office's web site although they have not updated some of their information and still have listed an investment of 10 million baht to receive permanent residency which was only offered 5 years ago. The below is accurate at this time.  As long as you follow the requirements in items 1, 2 or 3 they will approve your visa for extensions every year for 1 year at a time for as long as you wish to live here.

(1) "The Investment Visa" You will need a valid passport  and need to open a Bank account in your own name at a Government Bank  when you visit Thailand. Then you will need to obtain a Non-Immigrant Visa from the Thai Embassy in your country for the purpose of investment. NOTE: You may also travel to Laos or Cambodia and visit the Thai Embassy there to obtain the visa or if you have entered Thailand on a Tourist Visa you may possibly get it changed to the Non-Immigrant Visa at the Bangkok Immigration Office when you show them the information that you have deposited the funds in a government bank.  (You will need to deposit 3,000,000 (Three million baht) into a fixed deposit in your own name) which would be a letter from them stating that you have 3 million baht in a 1 year fixed deposit with them and a copy of your bank book.  Bangkok Immigration Office is the office that approves or denies all long term visas. Take note that the requirement is for government banks only, not private banks.  As long as you retain your fixed deposit, you can get a letter from the bank each year and get your visa renewed for another 1 year period. You can always change your visa to item #2 or #3 at a later date with no problem from any Immigration Office.
NOTE: They call it an "Investment Visa" but it is anything but an investment for you. They pay you 0.5% so think about that before you decide to go that route.

(2) "The Marriage Visa" A little more paperwork than the Investment Visa but eliminates the 3 million baht requirement which is quite good since the government bank only give 0.5% interest. For the marriage visa you would need to be legally married to Thai citizen and need to have at least 200,000+ baht ( $5,000 USD at current exchange) in a joint account with your wife.
NOTE:  The new required amount this year is 400,000 baht, double the amount from last year. You may take note of this and consider that this is a very unstable system that the government has for visas and things change every year it seems.
 You would need to have a copy of your passport, a letter from the bank and a copy of your bank book to match the letter. Note: The letter must state that it is a joint account in the names of you and your wife and the current balance of the account not less then 400,000 baht. You will also need a copy of your marriage papers, yours wife's ID card and House Registration book which she will already have. Please also note that the custom here is to be married in the village where the girls family lives with a ceremony conducted by the local monks. To make it legal you MUST get the proper papers from your Embassy and have them translated in Thai and registered with the Thai government and local Umper Office. Your wife and the Embassy can help you with this. Getting this set up the first time may seem a little difficult but with patience it really is quite easy and Thailand is making the paperwork less confusing for them and us. Once your set on the first visa for 1 year, the following renewals are a breeze. Just take the bank letter, bank book, copy of marriage certificate, wife's ID card and house book and that's it. They will stamp you for 30 days until the main department at the Immigration Office approves it for the next year. This is done every year at any Immigration Office near where you will be living.

(3) NEW UPDATE! "The Retirement Visa" You must be at least 50+ years old (The old requirement was 55+ years old) and then have according to the law, have 800,000 baht or more in any Thai bank in your name or proof of retirement funds of 65,000 baht a month. Now sometimes you may find that the small Immigration Offices don't quite follow the letter of the law as in the case of my friend. Note: that I stated above 800,000 baht in a bank account OR  proof of at least 65,000 baht a month in retirement pay which is basically the 800,000 divided by 12 months. It also can be the equivalent of both bank account and retirement pay to equal at least 800,000 baht that you would have for 1 year. It is supposed to be where they are sure you have money to live on each year that you are here. Some immigration offices may want to see both banks funds and monthly pay.

NOTE: With any type of visa you should check direct with the Immigration Office in Bangkok or the Thai Embassy in your country to make sure of the minimum money requirements at the time you are planning to come here. While they are more efficient now in processing the applications, it seems the Thailand government changes the rules and requirements too many times to keep track of.

If you are living here on a retirement visa or a marriage visa you may wish to use a bank that is more foreigner friendly such as Bank of Asia or Bangkok Bank which are both excellent banks and will treat you correctly paying you interest on your money. Some Government banks such as Krung Thai bank must despise foreigners and if you are allowed to open an account there they will pay you 0%. It would be wise to research anything and everything very carefully before doing anything connected with business in Thailand and make sure that you understand every detail. Any questions that you may have then you may be very wise to either have it in writing or forget it. If you are unsure of anything then it is always best to obtain proper legal advise before doing anything that involves your money.

Thai Embassy's web site in the USA

Office of Immigration Bureau

Board of Investment

Ministry of Foreign Affairs 

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