Why your tax isn't a flat percentage
South African income tax is progressive. Income is taxed in slices: 18% up to R245,100, then 26%, 31%, 36%, 39%, 41% and 45% on the highest earnings. Only the income within each bracket is taxed at that bracket's rate.
SARS then subtracts a tax rebate based on your age, which is why low earners below the threshold pay nothing at all.
Common questions
Everyone gets the primary rebate (R17,820 in 2026/27), which is subtracted from your tax. People 65+ get an extra R9,765, and those 75+ a further R3,249.
Below the tax threshold, no tax is due. For 2026/27 that is R99,000 a year if under 65, R153,250 from 65, and R171,300 from 75.
Your marginal rate is the bracket your last rand falls into (18–45%). Your effective rate is total tax over total income — always lower.