Tax calculation not right

Question

I have a problem with my Magento installation. I have set up the website with 21% Tax. When you look in the cart, you see a completely wrong price calculation.

The excluding price is right, but the tax amount and including tax price are not. An example:

Total without Tax: €2.149,00
Shipping: €99,-
Tax: €468,47
Total with Tax: €2.699.29.

As you can see, nothing makes sense:

21% of €2.149,00 = €451,29.
21% of (2.149+99) = €472,08.

The total of the amounts: €2.149 + €99 + €468,47 is not: €2.699,29.

Can anyone please help with this problem? All the taxes are set up in the right way, and I am completely lost here.

Answer 1

If the blogpost in the comment doesn't affect you, I assume you have set your taxes wrong, or at least, not what you expect:

• your product price € 2.149,00 excludes tax
• your shipping price € 99 includes tax

See how it is calculated: € 2.149,00 * 1,21 + € 81,8182 * 1,21 = € 2.600,29

What you expect ist: € 2.149,00 * 1,21 + € 99 * 1,21 = € 2.720,08

How to fix this: Go to System -> Configuration -> Taxes -> Calculation and set "Shipping includes tax" to "No".