Combos API: Multi-Leg Parlay Trading on Bravado

The Bravado Combos API lets you buy multi-leg parlay positions across 2–10 markets via RFQ. Requires the trade.combos scope to quote, accept, and redeem.

Combos are multi-leg parlays, a single position that pays out only if every selected market resolves in your favor. Instead of placing separate orders across multiple markets, you submit a single combo order that bundles 2–10 YES outcome legs into one on-chain position. This API uses a Request-for-Quote (RFQ) model, meaning every price you receive is a firm, live quote from a real maker counterparty. To use the Combos API, your token must carry the trade.combos scope.

Why Bravado over the native endpoints

Polymarket has no multi-leg product. To express “all of these outcomes happen”, you buy each leg separately, which leaves you holding several independent positions rather than one parlay.

That distinction matters more than it first appears:

	Legging in manually	Bravado Combos API
Execution	One order per market	One position across 2 to 10 legs
Pricing	Whatever each book gives you, leg by leg	A single firm quote for the blended position
Partial fills	Some legs fill, some do not, leaving unintended exposure	The combo executes whole or not at all
Price certainty	Each leg can move while you fill the others	Quote is firm for its validity window

• A firm quote, not an estimate. A real maker counterparty prices the blended position and stands behind it. This is not a simulated midpoint derived from the books.
• No leg risk. Legging in manually means the market can move against you between the first fill and the last, and a failed leg leaves you exposed to a position you did not intend to hold.

Endpoints

Method	Path	Description
POST	/v2/trade/combo/quote	Request an RFQ quote for 2–10 legs
POST	/v2/trade/combo/accept	Accept a live quote and execute on-chain
POST	/v2/trade/combo/redeem	Redeem a resolved-win combo to pUSD
GET	/v2/trade/combo/positions	List the user’s combo positions

RFQ model

The Combos API is built on a Request-for-Quote flow. When you call /combo/quote, a real maker counterparty prices the blended position and returns a firm quote, not an estimate or a simulated midpoint. That quote is valid for approximately 8.5 seconds from the time it is issued.

You must call /combo/accept before the expires_at timestamp in the quote response. If you wait too long, the API returns a 410 QUOTE_EXPIRED error. When that happens, re-quote rather than retrying the stale accept, the underlying market prices may have moved, and the maker needs to re-price the position.

POST /combo/quote  →  POST /combo/accept (within ~8.5 s)  →  (event resolves)  →  POST /combo/redeem

Key units

Field	Unit	Example
leg_position_ids	2–10 YES position token IDs	["7248…", "9931…"]
notional_usd	US dollars to spend	5
price_cents (response)	Cents per blended YES share	2
taker_shares (response)	Combo shares you receive	66.5
payout_usd (redeem response)	pUSD paid out on win	50

All numeric fields in API responses are returned as JSON strings, not numbers. Parse them accordingly before performing arithmetic.

Combo positions

After a combo is accepted on-chain, it appears in GET /combo/positions with one of four status values:

Status	Meaning
OPEN	All legs are still active and unresolved
PARTIAL	One or more legs have resolved (win so far)
RESOLVED_WIN	Every leg resolved in your favor, eligible for redeem
RESOLVED_LOSS	At least one leg resolved against you, position is worthless

Use the combo_position_id returned from /combo/positions when calling /combo/redeem if you did not retain the original combo_order_id from /combo/accept.