Coupon Discount Calculation Seems Wrong

When I check out, using a 10% off coupon, the system seems to calculate the discount wrong:

Sub-Total: $69.90
Regular Shipping (Regular Shipping): $14.95
Discount Coupon: SHH : -$7.34
Maine Sales Tax 5%: $2.80
Total: $80.31

The discount should be -$6.99

I can't seem to figure out where the discount is coming from. $7.34 is 10% of what exactly? It's not 10% off of the sub-total, it's not 10% off of the sub-total plus tax, etc.

Has anybody else experienced this? Any help would be greatly appreciated!!

Kevin

PS If you are really bored, you can test it at newtonsuniverse.com - use the coupon SHH

I tried to test your coupon, but it looks like the code has expired... say, where did you get that "tell a friend" module; is it the unwishlist?

No-one with a solution? I have the same problem and do not for the life of me understand where the discount is coming from.

Example: with a 10% discount

Products total: 431,00 NOK
Shipping: 95,00 NOK
Discount code: xxxxxx: - 46,37 NOK
Norwegian MVA (taxes of 25%): 51,72 NOK
Total order: 457,04 NOK

This does not make any sense, discount should be 43,1 NOK
And even if I sum up the order myself, adding 431 + 95 and deducting the discount, I end up at 479,60 NOK Any clue as to what is happening? Do I have my taxes set up wrong?

My site is at https://www.igroshage.no/zenshop - it is LIVE and I regret to inform you, it is only in norwegian.
Running 1.3.6

I've been stumped on this one as well... and I wasn't able to test your site very easily (I don't know Norwegian, and perhaps that threw me, but I also couldn't figure out what your coupon code was or where I was supposed to enter it).

What we did when we had the problem was to adjust the percentage amount of the coupon until it approximated the actual discount we wanted to give... So I think we ended up setting up a discount for 23% in order to get our cart to calculate a 25% discount. Perhaps in your situation you could offer 8% or something like that? I know it's not perfect (10% sounds like a nicer incentive), but it might work as a quick fix until the coupon system is fixed so that it makes more sense.

The less quick fix, which I haven't done yet, is to write some code that will process the coupon as you expect it to be processed.

kevinhankens:

Sub-Total: $69.90
Regular Shipping (Regular Shipping): $14.95
Discount Coupon: SHH : -$7.34
Maine Sales Tax 5%: $2.80
Total: $80.31

The discount should be -$6.99

You probably have the Discount Coupon Module set to include Shipping. Check the coupon module settings:

Admin > Modules > Order Total > Discount Coupon

Also, I believe the Sort Order may play a role

HTH :smile:

Thanks for the input! I have a testrun of 1.3.7 up now, and it seems to fix the problem for me - don't know if it was a fix in the cart or if it is because the testsite is still running clean, without any mods or addons except for language running. So now its just a matter of finishing the upgrade ASAP...