Zen Cart custom software development, Zen Cart modules, Zen Cart Expert eCommerce with Zen Cart!

osCommerce™ Customization

Please note: This is the legacy osCommerce page for releases 2.2, 2.3 and 3.0. For current osCommerce information, please see my osCommerce page.

The main focus of my business is Zen Cart Modules, but I have ported some of my most popular work to osCommerce. I post as swguy on the osCommerce forum.

Want to see my software in action? Take a look at my osCommerce Videos.

If you've never installed an osCommerce mod before, please read my Guide to Mod Installation on osCommerce.

The perfect companion for my modules Quantity Discounts and Better Together is Discount Preview, which lets you see the discounts on the Shopping Cart page. Without this module, your customers must wait until the checkout payment page to see their discounts, which many e-commerce experts believe reduces the likelihood of completing a sale.

Responsive osCommerce and PHP7

Responsive osCommerce (aka Phoenix) is a community release which necessitates some tweaks to my software.
  • The file includes/database_tables.php has been removed from this version, so you'll have to fix the table name definitions. Add to the top of includes/modules/order_total/my_module the following:
    if (!defined('TABLE_PRODUCTS')) { 
      define('TABLE_PRODUCTS', 'products');
    if (!defined('TABLE_PRODUCTS_TO_CATEGORIES')) { 
      define('TABLE_PRODUCTS_TO_CATEGORIES', 'products_to_categories');
    if (!defined('TABLE_TAX_RATES')) { 
      define('TABLE_TAX_RATES', 'tax_rates');
  • PHP5 style constructors are now required in PHP7. So change the constructor name to __construct. For Better Together, this means changing
            function ot_better_together() {
            function __construct() {
  • PHP7 now complains about missing defined variables, so do an early exit if the module is not installed right after the title and description are set. For Better Together, this would be
           $this->enabled = ((MODULE_ORDER_TOTAL_BETTER_TOGETHER_STATUS == 'true') ? true : false);
          if (!$this->enabled) return; 

osCommerce 2.x

Notes on osCommerce updates: please see my instructions on The Cart Blog.


Free software, original works. Donations appreciated.

Download Link to Support Thread Relevant osCommerce Version Help
Quantity Discounts for osCommerce 2.x Support Thread 2.2, 2.3, 2.4 Quantity Discounts for osCommerce
Better Together for osCommerce 2.x Support Thread 2.2, 2.3, 2.4 Better Together for osCommerce
Better Together also has a whole group of supporting add-ons I call The Better Together World for osCommerce
Better Together Promotional Page for osCommerce 2.2
Better Together Promotional Page for osCommerce 2.3
Support Thread 2.2, 2.3, 2.4 Better Together Promotional Page for osCommerce
SysCheck osCommerce 2.x Support Thread 2.x SysCheck for osCommerce


Shrink-wrapped commercial software, generally priced in the $30-$60 range.

Extension Name More Details
Discount Preview Discount Preview for osCommerce allows your customers to "preview" on the Shopping Cart page the discounts they will receive on the Order Confirmation page. It is designed to work in conjunction with my Better Together and Quantity Discounts contributions, as well as Big Spender for osCommerce, Discount Chooser for osCommerce, Big Chooser for osCommerce and Table Discounts for osCommerce. For more details, see the osCommerce Discount Preview page.
Discount Chooser The Discount Chooser Mega Module allows you to flexibly create product based (rather than dollars spent based) discounts with a built in admin panel. Somewhat less flexible than Big Chooser, but with the simplicity of point and click configuration.
(Note: Discount Chooser was formerly called Free Gift Chooser; the name was changed to more accurately reflect its capabilities.)
Better Together Admin Tired of having to edit the setup() function to add osCommerce Better Together discounts? The osCommerce Better Together Admin gives you a user interface to add every type of linkage that Better Together supports.
Big Spender Big Spender for osCommerce is dollar based discounting. Spend over a certain dollar amount, get a discount on other products / receive other products free.
Big Chooser Big Chooser for osCommerce is product based discounting. Buy multiple items, get a discount on other products or combinations of products, or receive other products or combinations of products free.
Table Discounts osCommerce Table Discounts allows you to offer quantity discounts with multiple discounting schedules depending on category, product or manufacturer.
Buy Both Now Buy Both Now for osCommerce Adds a one-click purchase button to your Better Together offers on the product info page for products which do not have attributes.
Add Both to Cart Add Both to Cart for osCommerce allows a shopowner display the Better Together Promotional Page with a one-click add for Better Together pairings of products which do not have attributes.
Better Together Offers on Listing Pages Better Together Offers on Listing Pages for osCommerce allows a shopowner to display currently available Better Together offers on all osCommerce 2.2 Listing Pages (Category Listings, Search Results, and Manufacturers Page). For a screenshot, see the Better Together Offers on Listing Pages for osCommerce help page.
Checkout Candy Checkout Candy for osCommerce allows a shopowner to add a last minute call to action on the shopping cart page and the first checkout page. Although any desired message may be added, this module is ideally suited to interoperate with Better Together; it will display any outstanding Better Together offers based on the content of the cart. For more details, see the Checkout Candy page.

Tips and Tricks

osCommerce 3.0

The osCommerce 3 project was a rewrite which seems to have been abandoned. If you still want to read about it, please see my osCommerce 3 page.

More Useful osCommerce Links