We have a problem with the tax not beeing calculated correctly if a discount coupon is beeing used (either in percentage or amount). We show the prices in the cart including Tax, Shipment cost is inculding tax as well. We have a taxrate of 21%.
Poduct amount Price Subtotal
Shoes 1 EUR 39,95 EUR 39,95
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Subtotal EUR 39.95
Couponcode test 10% EUR -4,00
Shipment costs EUR 5,95
Total EUR 41,90
Total tax EUR 6,97
The total tax should be EUR 7,27. I tried several settings in Onepage checkout (although the default is salesPriceCoupon). We have a tax rule of VAT tax + 21% in Virtuemart applied to all shoppergroups and all products.
I can't seem to figure out what causes the Tax calculation to be incorrect. Without coupon codes, the calculation works as aspected.
How can we fix this problem?