Kalshi and Polymarket resolution: who decides the result?
Compare sources, determination times and dispute processes; distinguish UMA prediction markets from Chainlink up-down markets and Polymarket US.
The headline is only the beginning of the contract
Two markets can ask apparently similar questions while using different evidence, cut-off times or definitions. A market about an announcement is not necessarily the same as a market about an event having occurred. Reading only the short title can hide the distinction that ultimately controls settlement.
This comparison examines published resolution mechanics checked on October 21, 2026. It does not rate platforms by tested fairness, promise a payout time or establish that a product is available in every location. The earlier fee comparison addresses transaction cost; resolution concerns which result the contract ultimately recognises.
Kalshi: source agencies and determination
Kalshi's market FAQ says its markets team finalises the result after the official outcome is confirmed. It distinguishes the end of trading from determination and settlement. Waiting for a specified source to publish final data, or for a later determination time in the rules, can explain why a contract remains unsettled after the apparent end of an event.
A useful reading sequence is: identify the exact market, read its Rules and Important Information, record the named source and then check the determination time. A television result or another platform's settlement does not replace the source named in that contract. The general FAQ's timing description is not a guarantee for an individual market.
Polymarket: the resolution route depends on the market
Polymarket's current technical documentation distinguishes UMA-resolved prediction markets from Chainlink TWAP up-down markets. It is therefore inaccurate to describe every product carrying the Polymarket name as following one universal voting process. This section concerns the international documentation's UMA process, not a claimed rulebook for the separate US product.
For UMA markets, the documentation describes a proposed outcome and a two-hour challenge period. A dispute can trigger another proposal round; a second dispute can escalate to the Data Verification Mechanism and a token-holder vote. The documentation also gives separate treatment to exceptional or unresolved outcomes. Read the market's own conditions rather than treating a shortened help summary as the complete path.
| Question | Kalshi documentation | Polymarket documentation discussed here |
|---|---|---|
| What evidence controls? | The specified source agency and contract rules | The market's predefined resolution source and rules |
| Does an event ending guarantee immediate settlement? | No; determination can be later | No; proposal/challenge or another specified route may remain |
| Is one process universal? | Check the particular contract and product | No; UMA and Chainlink TWAP routes are distinguished |
Test the wording before comparing prices
Consider two hypothetical contracts: “Agency publishes a decision before Friday” and “Decision takes effect before Friday.” A decision published on Thursday but effective on Monday could satisfy the first description and fail the second. That illustration is not a claim about a listed market or a real dispute. It shows why apparently matching prices may refer to different questions.
Record the time zone, the treatment of postponements or revisions, and which version of a data release counts. If those details are absent or ambiguous, an attractive displayed price does not remove the uncertainty. Selling a position before determination is also a trade with another participant, not proof of the final result.
Keep resolution separate from withdrawal
A settled winning position, money credited to an account and a completed withdrawal are separate stages. The resolution documentation alone cannot establish deposit eligibility, banking speed or recoverability in a dispute. This article supplies a comparison of records and procedures, not a recommendation to trade or to bypass geographic restrictions.
Sources and checks
- Kalshi Market FAQs: source agencies, determination and settlement · Checked 2026-10-21
- Polymarket technical documentation: UMA and Chainlink TWAP resolution routes · Checked 2026-10-21
- Polymarket Help: disputes, datedApril5,2026; read alongside fuller technical documentation · Checked 2026-10-21