Tax not taking Gift Certificate into account

[srt9969]

Hi all,

I've searched the forum, but any answer to this is well hidden.
My checkout calculations are working fine, except when a gift certificate is applied to the cart. Then, all the maths is correct, including final total, however the VAT figure is as if no gift certificate was applied.

Example:
Subtotal 252.17
Gift Voucher -5.00
Discount 5% -12.36
Shipping 3.48
VAT 17.5% 36.20

Total 238.29

The VAT should show 35.49 (VAT on 238.29)

It's actually showing VAT on 243.04, which comes from:

(252.17-12.61(the 5% discount, ignoring the GV)+3.48)=243.04

So, I guess I have 2 questions:

1. How, and where, is tax calculated, and

2. How do I fix it?

Thank you, for any light you can shed,

Regards,

Sean

[wilt]

Hi,

Gift Voucher redemption is not subject to VAT.

Think of the redemption as another form of payment.

[srt9969]

...doh.

So, I can't apply the GV before the discount.

Sean