Stake Limits

Every market carries a minimum and maximum stake. Read them over REST with GET /events/{eventId}/markets?expand=stake_limits. On the WebSocket market channel, they arrive with every market_updates frame, and stake_limit_update tells you when they change.

"stake_limits": [
  {
    "pricing_provider_id": 1,
    "participant_id": null,
    "min_stake": 10,
    "max_stake": 1000
  }
]

Minimum stake

min_stake is exactly what it sounds like: the smallest stake the market accepts. Bets below it are rejected with 400.

Maximum stake depends on the price

max_stake is a single limit that caps your stake at high prices and your potential profit at low prices, so it is not always the maximum you can stake. How it translates into a stake cap depends on the decimal price you are betting at:

Price	What max_stake caps	Maximum accepted stake
>= 2.00	Your stake	max_stake
< 2.00	Your potential profit	max_stake / (price − 1)

At prices of 2.00 and above, a winning bet pays out at least as much profit as the stake itself, so the limit applies to the stake directly. Below 2.00, each unit staked wins less than a unit, so the limit shifts to your potential profit, and you can stake more than max_stake.

Worked example

With max_stake: 1000:

Price	Maximum stake	Potential profit at max
3.00	1,000	2,000
2.00	1,000	1,000
1.50	1,000 / 0.50 = 2,000	1,000
1.10	1,000 / 0.10 = 10,000	1,000

Bets above the effective maximum are rejected with 400.

Compute the cap before placing

Work out the maximum accepted stake client-side before calling POST /bets:

If price >= 2.00:  max_accepted_stake = max_stake
If price <  2.00:  max_accepted_stake = max_stake / (price - 1)

Scope and shape

• Limits are per market. On participant-scoped markets (e.g. player props), the entry carries the participant_id it applies to; on event-scoped markets participant_id is null.
• pricing_provider_id is always 1 (Vertex), consistent with the rest of the API.
• Limits are specific to your API key. Different partners may see different values on the same market.

Keeping limits current

Limits change as an event approaches and during play. The integration pattern mirrors prices:

1. Baseline over REST: fetch expand=stake_limits alongside selections when you load an event's markets.
2. Read them from market_updates: each frame carries the market's current stake_limits, including the first frame after a market opens. suspended_market_updates never carry them.
3. Listen for stake_limit_update: it arrives on the market channel whenever a market's limits change.
4. Re-baseline when in doubt: the REST read is the authoritative source for the limits in force; after a reconnect, re-fetch rather than trusting cached values.