> ## Documentation Index
> Fetch the complete documentation index at: https://docs.vatic.trading/llms.txt
> Use this file to discover all available pages before exploring further.

# Fee Structures

> Understanding legacy vs. April 2025 Polymarket taker fees.

Vatic API exposes two fee calculation namespaces to match both of Polymarket's fee eras.

## Legacy fees (`/api/v1/fees/*`)

Used for markets created before April 2025.

**Formula:** `fee = feeRate × p^exponent`

Where `p` is the average price of the trade.

| Category            | `feeRate` | `exponent` | Maker rebate |
| ------------------- | --------- | ---------- | ------------ |
| Crypto (intraday)   | 25%       | 2          | 20%          |
| Sports (SEA, NCAAB) | 1.75%     | 1          | 25%          |

For a BUY order, fees are deducted from the shares received. For a SELL order, fees are deducted from the USDC received.

## April 2025 fees (`/api/v1/new_fees/*`)

Applies to markets created under Polymarket's updated fee structure.

**Formula:** `fee = C × feeRate × p × (1 − p)`

Precision: 5 decimal places.

| Category      | `feeRate` | Maker rebate      |
| ------------- | --------- | ----------------- |
| `crypto`      | 7.2%      | 20%               |
| `sports`      | 3.0%      | 25%               |
| `finance`     | 4.0%      | 25%               |
| `politics`    | 4.0%      | 25%               |
| `economics`   | 5.0%      | 25%               |
| `culture`     | 5.0%      | 25%               |
| `weather`     | 5.0%      | 25%               |
| `general`     | 5.0%      | 25%               |
| `mentions`    | 4.0%      | 25%               |
| `tech`        | 4.0%      | 25%               |
| `geopolitics` | —         | — (no taker fees) |

## Trade estimate endpoints

Both fee namespaces expose a `/trade-estimate` POST endpoint that returns the exact fee and net outcome for a given BUY or SELL trade. Provide either `eventId` or `eventSlug` to have the fee config resolved automatically from Polymarket's Gamma API.