SARS Interest Calculator

SARS charges interest on all overdue tax at the prescribed rate — currently 11.25% per annum (repo rate + 3.5%). Interest accrues daily from the day after the due date until full payment.

Current rate: 11.25% p.a. (updated 2026-01-01)

How SARS Interest is Calculated

SARS charges interest on all overdue tax at the prescribed rate, which is calculated as:

Prescribed Rate = Repo Rate + 3.5%

Interest is calculated daily using this formula:

Daily Interest = (Principal x Rate) / 365

The current prescribed rate is 11.25% per annum. This rate changes whenever the South African Reserve Bank adjusts the repo rate.

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