The whole Perps documentation, in the parts that matter

Twenty-three pages of Polymarket Perps documentation. Here are the fourteen facts inside it that cost money if you skip them.

We have read the documentation. We have not traded the product.

Funding: the two facts that change your holding period

1. Funding settles every hour, not every eight

Polymarket samples a premium index off the order book every 5 seconds, averages those samples across the window, and settles the resulting rate against every open position once every 1 hour.source↗

Every intuition you carry over from another venue is calibrated to a three-times-a-day schedule. Here there are twenty-four settlements a day, and a position held overnight crosses eight funding events instead of one. Closing before the funding stamp and reopening after stops being viable: the stamp arrives every sixty minutes and the round trip costs two fees.

Funding is a line item in your break-even, not a rounding error. The funding page tracks what every market is paying.

2. The resting funding rate is not zero

The hourly rate is derived from an eight-hour formula that contains a fixed interest leg of 0.01%, clamped symmetrically at 0.05%, then divided by eight and capped at 4% an hour. Outside crypto, the whole thing is multiplied by 0.5.source↗

F_8h  = scale × (mean_P + clamp(0.0001 − mean_P, ±0.0005))
FR_1h = clamp(F_8h / 8, ±0.04)

A long that goes sideways is not free. The default direction of the system is longs paying shorts, and if your thesis needs three weeks to play out you are paying rent on all three of them. Funding is a straight transfer between traders — the protocol takes no cut — and it does not pause when the underlying market is closed.source↗

Margin: three rules that are not the ones you know

3. Maintenance margin is flat, and independent of your leverage

Maintenance margin is MM = Notional × MMR, where MMR = 0.5 / MaxLeverage. The rate is derived from the market’s maximum leverage, not yours: 2.5% of notional on a 20x market, 5% on a 10x market, for every position on it.source↗

Choosing 5x instead of 20x does not lower the floor you get liquidated at. It raises your starting point above a floor that never moves. It still improves survivability enormously, and it makes liquidation distance a clean function of your leverage alone. The arithmetic at each setting is here.

4. Risk tiers apply to your whole notional, not bracket by bracket

Each market carries a ladder of risk tiers that lowers the maximum leverage as a position grows, and the applicable cap governs the entire position rather than only the portion above the threshold. An order that would push you into a tier your current leverage setting violates is rejected with invalid_leverage.source↗

On a venue with bracketed tiers, growing a position past a threshold gently dilutes your effective leverage. Here it dilutes nothing — it invalidates your setting outright and the add is refused. Lower leverage first, then add. If you are scaling in and cannot work out why the last clip bounced, this is almost always the reason.

5. The pre-trade check prices your worst case, including resting orders

The margin check does not evaluate the position you hold. It evaluates WorstCaseSize = max(|Position + OpenBuys|, |Position − OpenSells|) — the larger of what you would hold if every resting buy filled and what you would hold if every resting sell filled.source↗

Unfilled orders consume margin. A ladder of resting bids you left up “just in case” is charged against you at full size right now, and it is a common reason a new order is rejected on an account that looks like it has plenty of room. Cancel the ladder and the room reappears. Withdrawals get the same treatment: equity after the withdrawal must still clear initial margin, so you cannot withdraw yourself into a margin call.source↗

Prices and sessions

6. Mark is a median of three candidates, and last trade margins nothing

Mark price is Mark = median(C1, C2, C3), recomputed every 200ms. The candidates are a smoothed order book mid built on a 150-second EMA of the mid-to-index gap, a local activity median of best bid, best ask and last trade, and an aggregated external mark. If a candidate degrades it falls back to the index price.source↗ The index itself is a weighted average of Pyth, Chainlink Data Streams, Hyperliquid, republished on the same 200ms cadence.source↗

The last trade price — the number the chart draws — is used for margining exactly never. Mark computes your unrealized PnL, your margin state, your liquidation trigger and your take-profit and stop-loss triggers. Because mark takes a median of three independently-built numbers, pushing one of them around with a thin-book print moves nothing: the median selects a different candidate.

“The chart never touched my liquidation price” is a coherent sentence.

A stop-loss can trigger on a wick you never see, and fail to trigger on one you do. The full mechanism, candidate by candidate, is here.

7. Market sessions change the feeds and nothing else

There are 5 session categories — regular, overnight, weekend, disrupted, halted. A session changes 2 things: which external feed set computes the index price, and the third candidate inside mark price. If no feed set is defined for the current category, the overnight set is used.source↗

What a session does not change: funding, margin and leverage tiers, order matching, liquidation triggers. Your Nvidia perp keeps matching orders at two on a Sunday morning, keeps charging funding every hour, and can liquidate you while the exchange the stock actually trades on is dark. What round-the-clock stock exposure really means.

Liquidation: four things worth knowing before you need them

8. A cross liquidation blocks new orders on every market

Cross and isolated are evaluated independently, each against its own equity. Under isolated margin a liquidation closes only the affected position and new orders are blocked on that market alone. Under cross, the system evaluates the whole account, can unwind more than one position, and blocks new orders on every market the account trades.source↗

The blast radius is the entire account. A blow-up on a small speculative cross position freezes your ability to manage a large, healthy one on a different market at precisely the moment you most want to touch it. The web app defaults to isolated; cross is opt-in through the API’s leverage configuration.source↗ The two modes compared properly.

9. Liquidation orders have no protective spread

A liquidation is executed as reduce-only, immediate-or-cancel, market-priced. There is no protective offset from the mark price. An isolated position is closed in full; a cross account is unwound one position at a time until it recovers.source↗

Your exit is a market order into whatever happens to be resting, at the worst possible moment, with no floor on how far it walks. Set your own stop well above the liquidation level: a stop you choose is a market order you control the timing of.

10. Below two-thirds of maintenance margin, the book is skipped

If equity falls to equity below two-thirds of maintenance margin, the exchange stops working the order book and the insurance fund absorbs the position directly — but only if the fund remains at or above its own maintenance margin afterwards.source↗

Past that threshold your position is no longer being sold into a market at all. It is being taken over. And the backstop is conditional: when the fund cannot safely take a position, the system reaches for the next mechanism instead.

11. Auto-deleveraging can close a position of yours that is winning

When the insurance fund cannot absorb a liquidation, the position is closed against counterparties on the other side, ranked by AdlIndex = ProfitRatio × Notional / Equity where the profit ratio is Mark / Entry for longs, Entry / Mark for shorts. Most profitable and most leveraged go first. Isolated positions are filled at the liquidated position’s bankruptcy price and cross positions at the mark price frozen when the liquidation began. A counterparty is only ever reduced, never flipped or increased, and auto-deleveraging charges no fee.source↗

This is the only rule in the documentation where somebody else’s mistake reaches into your account. You can be right, be up, be well margined, and have the position cut anyway because you were the most attractive counterparty on the book. Being both very profitable and very leveraged puts you at the top of the queue. Take leverage down once a trade has worked.

Plumbing: three facts that bite at the edges

12. Self-trade prevention cannot be disabled

Self-trade prevention is always on and runs in one mode, CancelMaker: If your taker would match your own resting order, the resting maker is cancelled and the taker keeps matching against everyone else.source↗

If you quote both sides of a market, a taker order of yours will silently delete your own resting quote on the other side. Not reject the taker — cancel the maker. Anybody running a two-sided strategy needs to expect resting orders to vanish without an error, because from the API’s point of view nothing went wrong. The full order type, time-in-force and flag matrix is here.

13. The exchange is hybrid: off-chain matching, on-chain state roots

order book, matching, risk checks, margin, funding all run off-chain. Deposits, Withdrawals, State root commitments settle on Polygon, in pUSD. There is no transaction per trade. The exchange periodically commits its offchain ledger onchain so observers can verify reported state.source↗

You get order book latency rather than block latency, and you do not pay gas to place an order — but the risk engine, the matching and your margin are custodial infrastructure, not something you can independently verify trade by trade. The state root commitments are the compromise: they let an observer check the ledger the exchange reports, periodically, rather than continuously.

14. Your account is keyed by the EOA, not the Safe

A Perps account is identified by the EOA base address that signs createProxy, not by the proxy or Safe address you may be used to seeing as your Polymarket identity.source↗

Anybody querying balances or positions programmatically, or reconciling an address against an explorer, needs the signing address rather than the contract address. Get it wrong and you get an empty result set and no error message.

What the docs do not tell you

Everything above is documented. The following is not. These answers only come from putting size through the system, and Bookie has not.

• ▸Real liquidity depth. The funding formula walks $1K of notional on each side of the book to build its impact price, which tells you what the mechanism assumes, not what the book holds. How deep the book actually is on the thirty-ninth market at three in the morning is unknown until you look.
• ▸Actual slippage on a market order. Documented fees are exact. Slippage is not documented anywhere, and on a leveraged position it can dwarf the fee.
• ▸How the interface behaves. Where the leverage selector lives, whether the margin mode is obvious before you commit, what the liquidation price display actually shows, how a rejection is surfaced.
• ▸Whether funding spikes in practice. The hourly cap is 4%, which is enormous, and the resting rate is tiny. Where the real distribution sits between those two — and how often it goes anywhere near the cap — needs history, not a formula.
• ▸How often auto-deleveraging fires. The mechanism is fully specified. Its frequency is not published, and frequency is the only thing that determines whether it is a curiosity or a risk you should size around.
• ▸Fill quality against the mark. Whether limit orders sit in the queue usefully, and how far a liquidation typically walks the book, are both observable and neither is written down.

The mechanics are knowable. The market quality is not. All fourteen on one screen, and the main guide tells it as a story rather than a list.