Thai Marriage Visas
When you decide to marry your Thai fiancée, you will need to acquire a Thai Marriage Visa. You will need a Thai Marriage Visa upon marrying your Thai fiancée and while living in Thailand with your Thai wife. To receive a Thai Marriage Visa, you can apply for one at an embassy. The brief requirements have been outlined with this guide on how you can obtain, or apply for, a Thai Marriage Visa; however, you should always contact an attorney native to Thailand and familiar with regulations to seek further legal advice, personal to your current situation.
UK Spouse Visas
If you so choose to bring your Thai wife to the United Kingdom, she would also need to obtain a UK Spouse Visa. Another visa that might be needed instead is the UK Fiancée Visa, which would be needed if you have not yet wed your Thai fiancée. Both of these UK visas have specific instructions and procedures that need to be followed before you can acquire one. Included are some of the processes you may need to go through, including having to speak with an immigration attorney. A registered immigration attorney will provide you with the appropriate legal advice.
K1 and K3 Visas
An American citizen who would like to have his Thai wife join him in the states would need to apply for the K3 Visa, although Thai fiancées need only apply for the K1 Visa. Individual United States Visas have their own procedures that need to be followed; so contacting an immigration lawyer who specializes in these would be very convenient. In addition, the K4 Visa is needed if there are any children that are involved.