Turn Cash on Delivery into a flexible, policy-driven surcharge instead of a one-size-fits-all cost.

This extension adds a dedicated Order Total module that applies a COD fee only when the customer chooses a payment method you define as COD (default: OpenCart’s cod.cod). Fees are controlled by rules you manage in the admin—per store if you run multiple storefronts.

What it does

Adds a “Cash on Delivery Fee” line to order totals when COD is selected and a rule matches.
Lets you charge a fixed amount or a percentage of the order base used for the rule (subtotal + selected shipping cost), so percentage fees can reflect delivery cost when you need them to.
Supports unlimited rules with sort order: the first matching rule wins, so you can stack general defaults and specific exceptions cleanly.
Each rule can target all customer groups or a specific group—ideal for wholesale vs retail or member pricing.
Min / max order total bands per rule let you waive or increase the fee by basket size (still based on subtotal + shipping as above).
Optional per-rule shipping filters: restrict a fee to certain shipping method codes, or leave them empty to apply for any shipping method.
Optional tax class on the fee so the surcharge follows your tax setup where applicable.
Multi-store: configure status, sort order, tax, payment codes, shipping allow-list, and the full rule table per store. If a store has no rules, the module can use rules from the default store as a fallback.
COD + shipping compliance: optionally define which shipping methods may offer COD at all. If you enable this list, COD payment options are removed at checkout when the customer picks a non-allowed shipping method—so you are not taking COD on carriers or methods you do not support.
Admin experience

Clear settings for extension status, sort order (with guidance to place the total after shipping when using percentage-of-order logic), tax class, and comma-separated payment codes (useful if you use a custom COD module or multiple COD-like methods).
Shipping methods are surfaced in the admin using live quote discovery where possible, with sensible fallbacks when quotes are not available—so you can still assign rules and allow-lists.
Languages included: English (en-gb), French (fr-fr).

Ideal for merchants who need COD surcharges that vary by customer type, order value, and delivery method, and who want per-store control without editing core files.

Note: Install/enable as an Extensions → Order Totals extension; ensure the event registered on install remains active so the optional “COD only for selected shipping” behavior works.