Post by takahashi1973 » Thu Oct 09, 2014 4:53 pm


I posted this once as a bug on Github dev platform for v 2.0

Problem is:
In many EU countries it is law or common to show all totals incl vat in B2C shops.
So you get for instance:

subtotal incl. vat
shipping incl. vat
some discount as % taken from subtotal + shipping incl. vat
some order extra charge incl. vat
The total including vat

First: oc 1.5.x does not have some setting for this incl. / excl vat logic
2nd: if we tweaked the shops totals logic we ended up with a serious round issue.

Had to do with currency logic AND how the incl. vat for products and totals is calculated.
IT should pick product price excl vat --> add the vat -- and ROUND
as it does on product prices in the shop if you set pricing to show incl. vat

but in totals it somehow does not use this logic hence if you have 10 x product X the round issue occured.

Can anyone update us on this regarding oc 2.0
Last edited by i2Paq on Thu Oct 09, 2014 5:00 pm, edited 1 time in total.
Reason: Title adjusted

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Thu Oct 13, 2011 11:41 pm

Post by SXGuy » Thu Oct 09, 2014 8:34 pm

Rounding issues are caused by the user generally forgetting to not round the excluding price. Plus a user not understanding how to reverse calculate a price including VAT. If you can show me an example of why you think there's a rounding problem that would be great.

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Sun Nov 08, 2009 2:07 am

Post by Johnathan » Thu Oct 09, 2014 10:51 pm

I have a Display Order Totals With Tax extension, that can display any Order Total line item including/excluding tax. It doesn't fix the rounding issue, since that's internal to OpenCart, but it should work for your requirement.

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Fri Dec 18, 2009 3:08 am

Post by fabrizio » Fri Oct 10, 2014 2:47 am

Hi all!.
First of all thank you for your hard work in developing the new OC version.
But here we are again!...The Rounding Issue!!

buy nº 10 Palm Treo Pro ( unit price $ 337.99 ) and you have $3,379.88..where are 2c?
buy nº 100 and you have $33,798.80, not good! where are 20c

Imagine if i have product with unit price of $0.04c...$0.23c..$0.33c as unit prices and orders in thousands for each item, what happen?.
The rounding problem is still here.

We cannot have a cart with wrong math folks, not to mention serious legal issues!!.

@SXGuy: the rounding issue isn't caused by caused by OC. As Takahashi writes "should pick product price excl vat --> add the vat -- and ROUND "...simple as that!.
With this logic we get rid of this issue and other bad side effect as Paypal not matchinf the total etc etc.

have a nice day




Thu Apr 04, 2013 1:06 am
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