Author Topic: tax calculation is wrong after changing discount/fee  (Read 2008 times)


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tax calculation is wrong after changing discount/fee
« on: June 03, 2009, 15:02:10 pm »
Hi, when a customer buys something of say €40,00, and he chooses to pay with iDeal (dutch payment system) an extra fee of €2,00 will be added, so the total amount of the order is €42,00. now virtuemart has to calculate 19% tax over this, which is €7,98, which is also calculated so nothing wrong until now.

but when I change the fee in the order-administration, to let's say €5,00 (for example because I had some extra costs which have to be calculated with this order) the total order value now is €45,00 so the tax should be (19%) €8,55. however, now the tax is changed to €6,39 which is only the tax of the products (19/119 * 40).

so first the tax is calculated over the total value of the order (productprice+fee) but after changing something to the fee, the tax is only calculated over the productprice and not over the fee anymore.

the same problems occur when I add some discount instead of a fee, after changing he just only calculates the tax of the products while instantly also the fee/discount is counted in.

is this a bug in virtuemart or am I doing something wrong?


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Re: tax calculation is wrong after changing discount/fee
« Reply #1 on: March 31, 2010, 00:23:23 am »
Ohhhh, Me too,
If a customer uses their discount through the front end, my taxes are fine, but if they forget, and I add the coupon through the back end, the taxes do not alter at all, and still charge the original tax amount.
So, I might end up with an invoice for $20 with $10.50 supposed to be tax.


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    • Squangle ltd
Re: tax calculation is wrong after changing discount/fee
« Reply #2 on: March 31, 2010, 11:28:14 am »

If I remember correctly the database holds all the calculated data, if I have remember correctly then this must mean it is a bug and the data is not being recalculated when the order is changed.

You could have a look in the DB for the order to check this.
614869 products in 747 categories with 15749 products in 1 category.
                                             Document Complete   Fully Loaded
                Load Time First Byte Start Render   Time      Requests      Time      Requests
First View     2.470s     0.635s     1.276s          2.470s       31            2.470s      31
Repeat View  1.064s     0.561s     1.100s          1.064s       4             1.221s       4