FlexiFeesFee types
Last updated: September 23, 2026
FlexiFees calculates a fee seven ways: Fixed, Percentage, Percentage by cost, Per weight, Per unit of metafield, Percentage of metafield, and Formula. Every fee type works as a cart fee (one fee line for the whole cart) or as a per-product fee (calculated for each matching product and added up into one fee line).
The seven fee types compared
| Fee type | As a cart fee | As a per-product fee | Typical use |
|---|---|---|---|
| Fixed | One flat amount per order | Amount × quantity of each matching product | Delivery fees, small order surcharges, deposits per bottle |
| Percentage | % of the cart subtotal | % of each matching product's selling price × quantity | Order protection, tariff surcharges, fuel surcharges |
| Percentage by cost | % of the cart's total cost (Shopify's Cost per item) | % of each matching product's cost × quantity | Fees based on what the goods cost you, such as a percentage of wholesale |
| Per weight | Rate × total cart weight | Rate × unit weight × quantity | Heavy order surcharges, per-ounce or per-kilogram regulatory fees |
| Per unit of metafield | Rate × metafield number × quantity, summed over the cart | Rate × metafield number × quantity | Per pouch, per gram of sugar or plastic, per milliliter |
| Percentage of metafield | % of a metafield amount × quantity, summed over the cart | % of a metafield amount × quantity | A percentage of a wholesale or list price you store per product |
| Formula | Your calculation, run once for the cart | Your calculation, run for each matching product and summed | Combinations: fixed plus percentage, whichever is higher, tiers |
Which fee type do I need?
- The same amount every time: Fixed. As a per-product fee it multiplies by quantity: 0.65 per can × 10 cans = 6.50.
- A share of what the customer pays: Percentage.
- A share of what the goods cost you: Percentage by cost, which reads Shopify's Cost per item field.
- A rate per kilogram, gram, ounce or pound: Per weight.
- A rate per something only you know (pouches per can, grams of plastic per bottle): store the number in a metafield and use Per unit of metafield.
- A percentage of an amount you keep per product (a wholesale price that is not your Cost per item): Percentage of metafield.
- Two rules combined, a higher-of, or tiers: Formula.
Cart fee or per-product fee?
- Choose a cart fee when the charge belongs to the order as a whole: delivery fees, small order surcharges, packaging.
- Choose a per-product fee when the charge belongs to specific items: deposits, recycling fees, excise-style fees. It needs at least one product condition to know which items to charge, and it appears as one consolidated fee line.
Combining a fixed part and a percentage
Some rules have two parts, for example 0.65 per unit plus 10% of the price. You have two options:
- Two separate fees, a Fixed and a Percentage fee with the same conditions. Each shows as its own line, which helps when the two parts must be reported separately.
- One Formula fee,
0.65 * qty + 0.10 * price * qty, which shows as a single line.
Options on every fee
- Taxable toggle. Follow your Shopify tax settings or exclude the fee from tax. Details.
- Custom title. The exact wording customers see, including legally mandated labels.
- SKU. An optional code on the fee line for accounting and reporting.
- Fee limits (optional). Every fee type except Fixed accepts a minimum and a maximum, for example "2%, at least 1, at most 15". On a per-product fee the limits apply to the fee's total, not to each product.
When the calculation comes to zero
Products without a weight, without a cost, or without the metafield contribute 0. When a fee's total is 0, no fee line is added. One exception: a minimum on a cart fee applies even when the calculation comes to 0. On a per-product fee, the minimum never creates a fee on its own.
The first cart with a new amount. Calculated fees produce amounts Shopify has not seen before. The first time a new amount appears, Shopify can take a few seconds, occasionally up to about a minute, to accept the new fee line; FlexiFees retries automatically, and the same amount is instant from then on. Fixed fees are prepared when you save and appear immediately.
Related
- Metafields in FlexiFees: how to set up the numbers the metafield fee types and formulas read.
- All 35 conditions that decide when a fee applies.
- Use case guides showing these calculations on real fees.