When I manually calculate VAT I get a different VAT amount, why is that?
We use the correct formulae to calculate VAT as specified by the South African government. Please take a look at the correct instructions below to ensure you calculate correctly.
South African VAT calculation rules
Get the base line item amount excluding VAT - this can mean that you need to calculate & subtract VAT if your prices are specified as VAT inclusive.
Round to 4 decimals if required.
Apply any discount percentages to the VAT excluded line item amount.
Multiply the amount by quantity.
Add VAT to the total line item amount, round to the nearest cent.
The totals are calculated by summing the excluding VAT totals, and summing the VAT amounts separately. This might lead to a situation where a total amount added to the total VAT amount does not equal the total amount multiplied by the VAT percentage. This is correct behaviour.
Updated: Thu, 26 April 2018