Summary
If you make 2,045,992 บาท a year living in Thailand, you will be taxed 385,564 บาท. That means that your net pay will be 1,660,428 บาท per year, or 138,369 บาท per month. Your average tax rate is 18.8% and your marginal tax rate is 29.1%. This marginal tax rate means that your immediate additional income will be taxed at this rate. For instance, an increase of 100 บาท in your salary will be taxed 29.14 บาท, hence, your net pay will only increase by 70.86 บาท.
Bonus Example
A 1,000 บาท bonus will generate an extra 709 บาท of net incomes. A 5,000 บาท bonus will generate an extra 3,543 บาท of net incomes.