24/7
Can you short NVIDIA at 3am on Polymarket?
Yes — you can trade stocks 24/7 on Polymarket. NVDA-USD is a live market, short orders match at 3am, and nothing about the hour is special to the matching engine. What changes when Wall Street goes home is very small and very specific.
Short answer
You can short NVIDIA at 3am on Polymarket, and at 3am on a Sunday, because you are not trading the share — you are trading a perpetual future on its price. The order book, matching, hourly funding, margin checks and liquidations run continuously, 24/7.
When the underlying exchange is closed, exactly two things change: which set of external price feeds computes Index Price, and the C3 candidate inside Mark Price. That is the entire list. Your liquidation trigger is running just as hard at 3am as it is at noon.source
There are 24 equity markets in the catalogue and every one of them is awake right now.source
Can you really trade stocks 24/7 on Polymarket?
A perp is a contract that tracks a price. It does not own the underlying, it does not settle into the underlying, and it has no expiry — so there is no structural reason for it to observe the New York Stock Exchange’s opening hours. Polymarket’s matching engine does not know what day it is. It knows there is a bid and an ask.
The catch is that a perp still needs to know what the underlying is worth, every 200 milliseconds, forever.source That number comes from external feeds — Pyth, Chainlink Data Streams, Hyperliquid — aggregated as a weighted average across the selected feeds, after dropping stale prices and filtering outliers.source
At 2pm on a Tuesday, a feed for NVIDIA is reporting a price discovered by an enormous, deeply liquid, actively arbitraged market. At 3am on a Sunday, that market has been shut for two days. The feed set has to change, because the old one has nothing to say. That switch is what Polymarket calls a session.source
The five Polymarket session categories
Every market is always in exactly one of five session categories. Three of them are about the clock and two of them are about things going wrong.source
| Session | What it means |
|---|---|
| Regular | The underlying is open and primary feeds are available. |
| Overnight | The underlying is closed but some external feeds may still exist. |
| Weekend | A calendar-based closed period with thin or absent external data. |
| Disrupted | External feeds are unavailable or failing sanity checks. |
| Halted | A trading halt or corporate-action freeze on the underlying. |
There is a fallback rule. If a market has no dedicated feed set configured for whichever category it is currently in, Polymarket uses the overnight set.source The overnight configuration is the default answer to “the usual feeds are not helping”, whatever the reason.
What happens when the stock market closes
Two things.
- Which external feed set computes Index Price
- The C3 candidate in Mark Price
Mark Price is the median of three independently-built candidates, and it is the price that drives your PnL, your margin and your liquidation.source C3 is aggregated external mark — a weighted average of external mark feeds, outliers filtered. C1 and C2 are built from Polymarket’s own order book and from Index, so a session change touches C3 directly and C1 indirectly through Index.
Mark = median(C1, C2, C3)
C1 = Index + EMA(Mid − Index) ← Index is session-dependent
C2 = median(BestBid, BestAsk, LastTrade)
C3 = aggregated external mark ← feed set is session-dependentWhich is a reassuring architecture. Take the median of three and one bad input cannot run away with the number. Every candidate also degrades to Index in the worst case, so a market with nothing but broken feeds converges on Index rather than on nonsense.source The full three-price mechanism is here.
What keeps running overnight and at weekends
None of the following pay any attention to the session.source
| System | Behaviour when the underlying is closed |
|---|---|
| Funding | Settles every 1 hour, all night, all weekend, unchanged. |
| Margin and leverage tiers | Same initial margin, same maintenance rate, same risk-tier ladder as at midday. |
| Order matching | The book stays open. Bids meet asks. Fills happen. |
| Liquidation triggers | Fires the instant equity drops below maintenance margin, with no overnight grace. |
Funding accrues while nothing appears to be happening. It settles every 1 hour regardless of session, and even a perfectly fair non-crypto market has a resting rate of +0.0006% an hour for longs from the fixed interest leg.source Hold a long equity perp across a weekend and every one of those hours is a funding window, during which the underlying did not trade at all. What every market is paying right now is on the funding page.
Disrupted, halted, and the strange bit
The two non-calendar sessions are easy to confuse and mean quite different things.
- Disrupted — External feeds are unavailable or failing sanity checks. This is a data problem. The underlying may be trading perfectly normally; Polymarket just cannot get a price it trusts.
- Halted — A trading halt or corporate-action freeze on the underlying. This is a world problem. The stock genuinely is not trading, because a regulator, the listing exchange or a corporate action has stopped it.
Both are still only feed-sourcing categories. Neither halts the perp.source
The contract on a halted stock keeps trading. The stock does not.
A pending-news halt is the moment when information is most asymmetric and price discovery in the underlying has been switched off — and the perp order book is open, with participants forming a view on what the stock reopens at. It is closer to a prediction market on the reopening print than to equity trading. Which is a very Polymarket thing for a product to become. Polymarket is quietly turning into Robinhood for degens.
During Disrupted or Halted, Mark is computed from the least reliable inputs it ever uses, while the liquidation trigger reads it at full strength. The median-of-three structure protects against one bad feed, not against the whole external picture being thin.source
Shorting NVDA: the actual numbers
| Parameter | Value |
|---|---|
| Symbol | NVDA-USD |
| Max leverage | 10x |
| Maintenance margin rate | 5.0% |
| Minimum notional | $10 |
| Max market-order notional | $500K |
| Max limit-order notional | $2.5M |
| Liquidation fee | 0.5% |
| Leverage cap at $750K notional | 5x |
At the full 10x, maintenance margin is 5.0% of notional and the adverse move that takes you from entry to liquidation is 4.76%.source NVIDIA has moved more than that on an earnings reaction more than once. Overnight, in a thin book, on feeds that are not the primary ones. The arithmetic at every leverage setting is here.
Maintenance margin does not depend on the leverage you chose. It is a flat rate derived from the market’s own maximum — 5.0% on a 10x market whether you opened at 10x or 2x.source Choosing less leverage does not lower the floor. It starts you further above it.
NVIDIA is not the only one. The catalogue carries 24 equity markets including SpaceX, Micron, SK Hynix, Apple, Microsoft, Alphabet, Amazon and Meta, all of them subject to the same session machinery.source The full list, with live parameters, is here.
What this means at 3am
The asymmetry is the real story, not the 24/7 headline.
- The price discovery behind your position is thinner. The underlying market is shut; the feeds still reporting are doing so with less to work from.
- Mark is being computed differently. A different feed set is behind Index, and behind C3.
- Your liquidation trigger is unchanged. Same condition, same maintenance rate, same instant response.
- The book you get liquidated into is the overnight book. Liquidation orders are market-priced and sweep whatever is resting.source
The risk does not scale down with the hour. The liquidity that absorbs it does. That is the trade you make when you open the position at 3am rather than at 3pm.
Set the exit when you set the entry. Nothing about a contract that never sleeps obliges you to stay awake with it. The full mechanics are on the main Perps page.
Questions people ask
Can you trade stocks 24/7 on Polymarket?
You can trade stock perps 24/7 — the order book, matching engine, funding and liquidation system run continuously, including overnight and at weekends. You are not trading the share itself; you are trading a perpetual futures contract that tracks its price. The contract never closes, even when the exchange behind the underlying does.
Can you short NVIDIA at 3am on Polymarket?
Yes. NVDA-USD is a live market with up to 10x leverage, and short orders match at 3am exactly as they do at noon. What differs overnight is that Index Price and the external candidate of Mark Price are computed from a different set of external feeds, and the book is usually thinner. At the full 10x, maintenance margin is 5.0% of notional and a 4.76% move against the short is enough to liquidate it.
What happens to a Polymarket stock perp when the market closes?
The perp does not close. Polymarket switches the market into a different session category, which changes which external feed set computes Index Price and the C3 candidate of Mark Price. Funding, margin requirements, leverage tiers, order matching and liquidation triggers are all unaffected.
What are the Polymarket Perps session categories?
There are five: Regular, Overnight, Weekend, Disrupted and Halted. Regular means the underlying is open and primary feeds are available; Overnight and Weekend are closed periods with progressively thinner external data; Disrupted means feeds are unavailable or failing sanity checks; Halted means the underlying has a trading halt or corporate-action freeze. If a market has no dedicated feed set for the current category, the overnight set is used.
Does funding still get charged when the stock market is closed?
Yes. Funding settles every hour, all day, every day, and session state has no effect on it. A stock perp held over a long weekend accrues funding for every one of those hours.
Can you be liquidated overnight on Polymarket Perps?
Yes. Liquidation triggers on the same condition at all hours — equity below maintenance margin, measured against Mark Price. Sessions do not pause, delay or soften the check, so an overnight move in the feeds that compute Mark can close your position while the underlying exchange is shut.
Does the perp keep trading if the underlying stock is halted?
Yes. A halt on the underlying puts the perp into the Halted session category, which only changes how Index Price and the C3 mark candidate are sourced. Order matching continues, so the contract on a halted stock keeps trading while the stock itself does not.