Thailand gets a lot of attention for a retirement destination. The weather is good, the cost of living is low, the people are friendly and your savings will go a lot further.
Furthermore, there is great cuisine, and many places to visit from the beaches of Koh Samui to the mountains of Chaing Mai.
Estimates for living in Thialand report that it costs about 35% to 75% of the cost of living in the United States. With rent being about 70% cheaper.
You should expect to live at about $1,500 USD to $2,000 USD per month. For sure you can live a cheaper lifestype, but it will be rather spartan.
If you live on between $3,000 to $5,000 USD per month, you can live a very easy and elegant lifestyle.
The Thai government expects retiress to live on about 65,000 THB per month, and its what they expect to see coming in your bank account monthly (or an annual lump sum) in order to maintain your retirement visa. However once you meet the financial requiremnt, it's up to you to decide how much you want to live on each month.
This retirement calculator spits out a typical budget depending on your income and where you want to live in Thailand.