A Polymarket market resolves when the outcome named in its rules is confirmed by its resolution source and reported on-chain through UMA's optimistic oracle; winning shares then redeem for $1 pUSD and losing shares for $0. On Nimb, read the rules before the price: the end date is not the resolution, and a market can keep trading after it.
Who decides the outcome of a Polymarket market?
Not Polymarket's traders, and not Nimb. Resolution is the process that decides a market's result under its rules and makes winning shares redeemable. On Polymarket it runs through the UMA oracle. Each market's rules name what will count. An oracle is the system that tells a blockchain contract what happened in the real world; Polymarket uses UMA's Optimistic Oracle, where a proposed result stands unless someone disputes it (Polymarket docs: resolution).
In short: a proposer reports the outcome and posts a bond; if nobody disputes it for 2 hours, it stands and the market settles. If someone disputes it, the question can go to a vote of UMA token holders. Most markets resolve without any dispute.
What are resolution rules and where do I find them?
Every market on Polymarket has a rules text under the market, usually headed "Rules" or "Market rules". It states:
- the exact question and what counts as Yes;
- the resolution source (an official body, a named data feed, a consensus of credible reporting);
- the deadline, with time zone;
- what happens in edge cases, such as a postponement, a tie or an event that is cancelled.
Read it before the price. Two markets with the same title can resolve differently: "Fed cuts in December" and "Fed cuts by December" are different questions, and "announced" is not "takes effect". A price is only a chance of the question as written.
What are the resolution source and the end date?
The resolution source is what the proposer and any voters must follow. If the rules say "according to the official results published by the electoral commission", a news call or an exit poll does not settle it. If the rules say a consensus of credible reporting, the answer can come faster, and is more open to argument.
The end date shown with a market is when the event is expected to be known or the window closes. It is not the moment of resolution. A market on "by December 31" can resolve Yes early, as soon as the event happens and is reported; a No outcome usually waits for the deadline to pass.
What happens if the result is disputed?
At the time of writing, the process on Polymarket runs like this (Polymarket docs):
| Step | What happens | Time |
|---|---|---|
| 1. Proposal | A proposer reports the outcome (Yes, No, or 50-50) and posts a bond, typically $750 pUSD. | After the event is known |
| 2. Challenge window | Anyone can dispute by posting a bond of the same size. | 2 hours |
| 3a. No dispute | The proposal stands and the market resolves. | About 2 hours after the proposal |
| 3b. First dispute | The proposal is discarded and a new proposal round starts. | Another proposal and 2-hour window |
| 4. Second dispute | The question goes to UMA's Data Verification Mechanism: a discussion period, then a vote of UMA token holders. | Debate 24–48 hours, vote about 48 hours |
| 5. Outcome | The side that was right gets its bond back plus half of the losing side's bond. | A disputed market takes about 4–6 days in total |
Since August 2025, most Polymarket questions use UMA's Managed Optimistic Oracle V2, in which only whitelisted addresses can propose an answer; anyone can still dispute (UMA docs: proposer whitelist). During resolution, Polymarket can also publish an "additional context" note on a market. Per its docs, such notes cannot change the question's intent, and UMA voters should take them into account.
The vote is the weak point: the final answer rests on UMA token holders, and critics have pointed out that voting power is concentrated. A disputed market is a market where the rules turned out to be readable two ways. That risk is in the price long before the dispute.
A rare third outcome exists: if neither answer applies under the rules, a market can resolve 50-50, and each Yes and each No share then redeems for $0.50.
Why is a market still open after its end date?
Because the end date passed, but the result is not official yet. Elections are counted, results are certified, governments are formed. Until the oracle settles the question, the shares keep trading, and the price shows what traders now expect the official result to be.
Nimb's own checks found a live example: the market on who will be Israel's prime minister after the next election was still trading on 2026-11-07, after its listed end date, with more than $30M traded over 30 days. When this happens, the Nimb market panel says:
The deadline has passed; the market is waiting for the official result.
Treat a price after the deadline as a reading of how the official result is likely to come out, under the rules as written, not of the event itself.
How and when do I get paid?
When the market resolves, each winning share can be redeemed for $1 pUSD and each losing share is worth $0. Redemption converts your winning shares into pUSD in your wallet; there is no deadline, so winning shares stay redeemable after resolution (Polymarket docs: redeem).
On Nimb, resolved positions appear in your portfolio, where you can claim them. You do not have to wait for resolution to take money out: while the market trades, you can sell your shares at the current price.
| Outcome | Each Yes share | Each No share |
|---|---|---|
| Resolves Yes | $1.00 | $0.00 |
| Resolves No | $0.00 | $1.00 |
| Resolves 50-50 (rare) | $0.50 | $0.50 |
What is an ambiguous rule and why does it matter?
An ambiguous rule is one that a reasonable person could read two ways once the facts are in: "a ceasefire" (announced or observed?), "leaves office" (resigns or is replaced?), "by March" (start or end of March, in which time zone?). When the wording is unclear, the price mixes two chances: that the event happens, and that the oracle reads the event the way you do. That second chance can cost you your whole stake even when you were right about the world.
What should you check in the rules before you trade?
Reading the market starts with its rules. Before you trade, check each line:
- Exact wording. Which verb, which threshold, which entity? "At least" or "more than"?
- Source. Which body, feed or reporting standard settles it? Is it likely to publish on time?
- Time zone and deadline. "By December 31" in ET, UTC or local time? Inclusive?
- Edge cases. What if the event is postponed, cancelled, tied, or partially happens?
- Early resolution. Can it resolve Yes before the deadline? Then a No position carries risk until the last day.
- Clarifications. Has Polymarket added context to the rules since the market opened?
More on this in how to read a market, and for the price itself, Polymarket odds explained.
Prediction markets are risky; you can lose your whole stake, including through a rule you misread. Nothing on this page is financial advice. Read the risks of prediction markets before you trade.
Last reviewed 2026-11-07 · Data from Polymarket · Not financial advice · Nimb is not affiliated with Polymarket.