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

# Combos API on Polymarket

> Buy multi-leg parlay positions across 2 to 10 Polymarket markets in a single on-chain position, priced by RFQ.

The [Combos API](/api/combos/overview) is supported on Polymarket. A combo bundles 2 to 10 YES outcome legs into a single position that pays out only if **every** selected market resolves in your favor.

This page covers what is specific to Polymarket. For the full request and response reference, see [Quote / Accept / Redeem](/api/combos/quote-accept-redeem).

## Why use a combo

Placing separate orders across several markets leaves you holding several independent positions, each of which can be filled at a different time and price. A combo is priced and executed as one position, so you either get the whole parlay at a known price or you get nothing.

## How pricing works

Combos use a Request-for-Quote model rather than the CLOB. When you request a quote, a real maker counterparty prices the blended position and returns a firm quote, not an estimated midpoint.

<Warning>
  A quote is valid for roughly **8.5 seconds**. Accept it before the `expires_at` timestamp or the API returns `410 QUOTE_EXPIRED`. When a quote expires, request a fresh one rather than retrying the stale accept: the underlying markets may have moved and the maker needs to re-price.
</Warning>

```
POST /combo/quote  →  POST /combo/accept (within ~8.5 s)  →  (events resolve)  →  POST /combo/redeem
```

## Polymarket specifics

* **Legs are position token IDs.** Each leg in `leg_position_ids` is a Polymarket YES outcome token id, the same identifier used as `symbol` on the [Trade API](/markets/polymarket/trade-api).
* **Resolution is per leg.** Every leg must resolve YES for the combo to pay out, and each leg settles through [UMA resolution](/markets/polymarket/uma-resolution). A combo is only redeemable once all of its legs have settled.
* **Collateral is USDC**, with `notional_usd` expressed in US dollars.

## Scope requirement

Your API token must carry the `trade.combos` scope. A key without it is rejected with `403 Forbidden`. See [Authentication](/authentication).

## Related

* [Combos API reference](/api/combos/overview)
* [Quote / Accept / Redeem](/api/combos/quote-accept-redeem)
* [Polymarket overview](/markets/polymarket/overview)