Fee Model

Building an integration? The API Integration Guide has the complete step-by-step fee computation with code examples. This page explains the concepts behind the fee model.

How fees work

CoW Protocol does not charge fees as a separate transaction. Instead, fees are embedded in the trade itself — deducted from the amounts you’re already swapping. This means:

Sell orders: fees reduce the buy amount you receive
Buy orders: fees increase the sell amount you pay

There is no separate fee transfer, no gas token deduction, and no invoice. If you’re looking for fee data for accounting, see Retrieving fee data below.

Fee types

Fee	What it covers	Applied to
Network costs	Gas fees for on-chain settlement	Sell token (always)
Protocol fee	CoW Protocol’s revenue (`protocolFeeBps` in quote)	Buy token (sell orders) / Sell token (buy orders)
Partner fee	Optional integrator fee (set via appData)	Buy token (sell orders) / Sell token (buy orders)
Slippage	Price movement tolerance (not a fee, but part of the pipeline)	Buy token (sell orders) / Sell token (buy orders)

Fee pipeline

Fees are applied in a specific order, transforming the raw spot price into the final signed amounts:

Spot Price (beforeAllFees)
  → after Protocol Fee
    → after Network Costs
      → after Partner Fee
        → after Slippage = amounts you sign

For the full pipeline with code examples and diagrams, see How Intents Are Formed.

Current protocol fee parameters

Fee	Rate	Applies to
Surplus fee	50% of surplus, capped at 0.98% of volume	Out-of-market limit orders
Quote improvement fee	50% of improvement, capped at 0.98% of volume	Market orders (swaps)
Volume fee	2 bps (standard) / 0.3 bps (correlated assets)	All orders

For full definitions and calculation formulas, see Fees (Governance).

Understanding the quote response

The /quote API response is the starting point for understanding fees:

{
  "protocolFeeBps": "2",
  "quote": {
    "sellAmount": "99937516653569264",
    "buyAmount": "191179999",
    "feeAmount": "62483346430736",
    "kind": "sell"
  }
}

Field	What it means
`sellAmount`	Sell amount after network costs deducted
`buyAmount`	Buy amount after network costs and protocol fee deducted
`feeAmount`	Network costs in sell token units
`protocolFeeBps`	Protocol fee in basis points (already reflected in `buyAmount`)

feeAmount is the network cost only — not the total fee. The protocol fee is already embedded in buyAmount (sell orders) or sellAmount (buy orders).

What you sign vs. what you see

For a sell order, the amounts signed into the order are:

sellAmount = spot price amount (= quote.sellAmount + quote.feeAmount)
buyAmount = minimum to receive after all fees and slippage

For a buy order:

sellAmount = maximum to pay after all fees and slippage
buyAmount = exact amount to receive (= spot price)

Retrieving fee data for accounting

On-chain, feeAmount is set to zero in the order struct. This confuses many integrators looking for fee data. The actual fees are embedded in the price difference between the quoted and executed amounts. To get fee breakdowns for a filled order:

1. Query the order details

curl https://api.cow.fi/mainnet/api/v1/orders/{ORDER_UID}

The response includes executedSellAmount, executedBuyAmount, executedSellAmountBeforeFees, and executedFeeAmount — these reflect the actual settlement values.

2. Query the solver competition

curl https://api.cow.fi/mainnet/api/v1/solver_competition/by_tx_hash/{TX_HASH}

This shows the solver’s execution plan including surplus generated and fees taken.

3. Use the CoW Explorer

Visit https://explorer.cow.fi/orders/{ORDER_UID} for a visual breakdown of the order’s fee components and settlement details.

For programmatic accounting, the TypeScript SDK and Python SDK provide typed access to order details including executed amounts and fees.

How Intents Are Formed — Full fee pipeline with code and diagrams
Fees (Governance) — Current fee parameters and definitions
Partner Fee — How integrator fees work
Error Reference — Fee-related errors (SellAmountDoesNotCoverFee)

Overview

How It Works

Benefits

Order Types

Flash Loans

CoW AMM

CoW Explorer

Integration

Architecture

API Reference

Core Reference

Auctions

How fees work

Fee types

Fee pipeline

Current protocol fee parameters

Understanding the quote response

What you sign vs. what you see

Retrieving fee data for accounting

1. Query the order details

2. Query the solver competition

3. Use the CoW Explorer

​How fees work

​Fee types

​Fee pipeline

​Current protocol fee parameters

​Understanding the quote response

​What you sign vs. what you see

​Retrieving fee data for accounting

​1. Query the order details

​2. Query the solver competition

​3. Use the CoW Explorer

​Related resources

How fees work

Fee types

Fee pipeline

Current protocol fee parameters

Understanding the quote response

What you sign vs. what you see

Retrieving fee data for accounting

1. Query the order details

2. Query the solver competition

3. Use the CoW Explorer

Related resources