Friday, 29 November 2013

Simple Opencart tutorial - shipping rate based on percentage of order

I was looking all over the internet for a free module to allow me set the shipping cost by a percentage if the order total was within a certain range; but to no avail :(
So I decided to do it myself.

Here's what I needed...

So for example:
  • If we set the shipping cost to be 10% of the order total, for an order total of £158.00, the shipping cost will be £15.80.
This is how I did it:

First of all,
  1. You have to download this free module -> Total Based Shipping ( )
  2. Follow the instructions on how to install the module (it's really easy)
  3. When you are done with that, navigate to catalog\model\shipping\standard_cost.php
    • NB: the standard_cost.php file will be a file from the module you just downloaded.
  4. Scroll to where you see, it should be around line 38 - 50
    • if ($cart_subtotal <= $data[0]) {
      if (isset($data[1])) {
      $cost = $data[1];}
  5. Then insert this
    • elseif ($cart_subtotal <= 200.00 ){
      $cost = $cart_subtotal*0.1;
      break; }

Simple! You just needed to add 3 lines of code.

The Module you downloaded in step 1 allows you to set specific shipping cost based on the order total. So we just included that code to calculate shipping cost based on a set percentage (in the above example, it's 10%. To calculate for a different percentage, just change the '0.1' in the code to whatever you want).

This was a quick fix and unfortunately, it's hard-coded. I'll try and improve on it so it can be modified from Opencart's back-end and update this post.

Please feel free to make suggestions or comments below. Thanks