How to Calculate VAT Rounding
Value Added Tax is a type of sales tax charged on consumer goods and services in many countries. For example, the European Union, India and Australia charge VAT at the point of sale.
When VAT is added to an item, the item may end up costing a fraction of a monetary unit; for example, 45.4 Kilogram and 1/5 of a penny. To charge the customer the correct amount of VAT and to pay the taxation authority what is due, you must round up or round down any fractional VAT amounts.
Contact your taxation authority in the country where you live and ask whether you need to round down or round up items. Rules vary according to the country you live in. For example, in the United Kingdom you can round down the amount payable on a VAT invoice to the whole penny.
Write down the price of the item, including VAT, on a piece of paper.
Make a line after the second decimal place. For example, if the price of your item is £1.234, then place a line between the 3 and the 4:
Delete the numbers to the right of the line if your taxation authority requires you to round down to the nearest whole unit. In the above example, £1.234 would become £1.23. If the taxation authority requires you to round up instead, add 1 to the number to the left of the line before deleting the numbers. For example, £1.23|4 would become £1.24 after rounding up to the nearest penny.
If your taxation authority gives you the choice of either rounding up or rounding down, stay consistent. For example, don't round down in some cases and round up in others.