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The e-commerce.

Calculating Sales Tax with Discount


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I have a tiered discount module installed where it is based on a percentage of the total. If there is no discount, the sales tax calculates fine. If the first discount level is met (ie, 3 items), the tax is off and it's a random amount, much below the correct value. If the second discount level is met, the tax doesn't calculate at all. I'm trying to find where the actual taxable total is calculated, without any luck. Any ideas?


catalog > includes > modules > order_total > ot_tax.php:


around line 30

while (list($key, $value) = each($order->info['tax_groups'])) {

if ($value > 0) {


$value is the tax amount - where is this calculated?




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