Fixed vs. Percent Fees

Each fee type defines how its value is calculated:

Fixed Fees

• amount_type = 0
• The assigned amount is used as a fixed per-unit fee.
• Total fee for the cart item is amount * qty.

Percent Fees

• amount_type = 1
• The assigned amount is interpreted as a percentage.

Calculation details:

• In cart/quote totals, the percent is calculated on the quote item's base unit calculation price.
• On the product detail page, the percent is calculated on the product's final price (display only).

Tip: if you use percent fees together with discounts, the effective base price used for calculation can differ based on Magento pricing rules and how the item price is calculated.