Shipping‐Tax Handling
Starting with EO v4.4.0, any tax on shipping is handled as a separate task. There are three (3) actions taken by Edit Orders' processing and each action's handling of the shipping-related cost and tax is slightly different:
- Initial entry, for the display of the
update_orderform. - An order "update" from that form.
- Adding a product to the order.
A primary element of the tax-handling update is the definition of a field in the database's orders table (shipping_tax_rate), in which EO initializes and/or saves the order's current shipping tax-rate. When a store updates its version of EO to v4.4.0 or later, the plugin's admin-level initialization creates that field in the database. That field's value defaults to null, indicating that no separate shipping tax-rate has yet been stored for the order.
While an admin has full control over the order's shipping_tax_rate, the order's shipping cost might be changed to 0.00 depending on the store's other configuration settings and/or products present in the order. This change will not result in the order's shipping_tax_rate being changed.
- If the order is updated to include all virtual products, the order's shipping cost is 0.
- If the store's configuration for Modules->Order Total->Shipping (i.e.
ot_shipping.php) identifies that orders over a certain value receive free shipping and the order-update or product addition result in a qualifying order, the order's shipping cost is 0.
Note: These processes cannot be overridden.
When an order's information is gathered from the database for the initial update-form display, EO checks the value for the order's orders::shipping_tax_rate field. If that field's value is not null, then the value has been previously recorded and that value is displayed. Otherwise, EO interrogates the order's current shipping-method to determine the initial tax-rate for the order and stores that value in the database.
When an admin-user uses EO to update an order, the shipping cost and associated tax-rate entries are used to update the cost and tax to be applied to the order. The display for that information entry is slightly different, depending on whether or not the store displays prices with tax (as identified by settings in Configuration->My Store).
In either case, when the order is updated, the tax-rate value entered is saved in the database as part of the order's update processing.
If the store displays prices without tax, EO's initial data-entry form presents the shipping-related values as:
The admin has full control of the tax-rate (a numeric field in the range 0 to 100, under the Tax column) and the shipping cost (a numeric field, under the Total Price column).
If the store displays prices with tax, EO's initial data-entry form presents the shipping-related values as:
For this case, EO uses a teeny bit of jQuery (based on built-in Zen Cart processing when entering product prices) to aid in the net vs. gross shipping cost. If the admin changes the shipping tax value, the gross shipping cost will change accordingly. Similarly, a change to the net- or gross-cost fields will result in a change to the other shipping-cost field, based on the value for the shipping tax.
When a product is added to an order, the previously-saved tax-rate is applied to the order's shipping cost.