Mr Sutthichai said the endorsement is expected to be published on the royal gazette in the next few days.
Tax payers who are low to middle income earners will benefit from the new rates, which provide tax reductions of between 5% and 50%.
Late last year the cabinet approved the new rates, which expand the previous five tax brackets to seven: 5%, 10%, 15%, 20%, 25%, 30% and 35%. The current rates are 5%, 10%, 20%, 30% and 37%.
The top tax rate falls to 35% of taxable income from 37%, while the tax exemption for annual income below 150,000 baht remains in place. The tax cuts are meant to lower payments to boost domestic consumption.
The new 5% rate will be applicable to those earning between 150,000 and 300,000 baht a year, with 10% for those who earn 300,001 to 500,000 baht, while 15% is for the 500,001 to 750,000 baht bracket, 20% is for 750,001 baht to 1 million baht, and 25% for those earning 1 million to 2 million baht. The 30% tax bracket is for those on 2 million to 4 million per year, while 35% is for over 4 million baht annually.