How Polymarket Works: Order Books, Fees and Resolution

The international site and Polymarket US are distinct products. Do not assume an account, API integration, funding rail or fee schedule transfers between them. The existence of a US product does not make the international product available in every jurisdiction. Check the official venue’s eligibility and account requirements before funding.

Use our venue comparison to separate the products. Tool listings that say Polymarket support refer to the international venue unless they explicitly document US support.

A standard binary market has YES and NO outcomes. An outcome share that resolves in your favor pays one unit of the contract’s settlement collateral; a losing outcome pays zero. Read the contract rules before assuming that every event uses this simple structure. Multi-outcome and combo products need separate analysis.

The price is a market-implied probability, not a verified forecast. A 40¢ YES price roughly corresponds to a 40% assessment before fees and trading frictions. If you buy 100 shares at that price, the purchase costs $40 before fees. A winning settlement pays $100 gross, not $140.

Polymarket’s current international trading documentation describes an order book, rather than the old generic automated-market-maker explanation. A bid is an offer to buy; an ask is an offer to sell. The displayed price can differ from the executable price for your order size.

A resting limit order may add liquidity. A limit order that crosses available prices may immediately take liquidity, so “limit” does not automatically mean “maker.” Inspect available depth, spread and partial fills. Large orders can consume several price levels, producing a different average entry price.

The international fee documentation applies a price-dependent taker formula to applicable markets. Makers currently have no protocol trading fee under that schedule. Category presets are a starting point; inspect the actual market’s parameters and any third-party builder charges.

Use the calculator below for a single-fill estimate or enter manually quoted costs. Fee-free trading still has possible spread, slippage and funding costs. Rewards and rebates have conditions and should not be treated as guaranteed profit.

A headline summarizes the event; the contract text identifies what actually settles it. Check the named source, cutoff, time zone, definition and treatment of ambiguous cases. Two markets with similar titles can resolve differently.

Closing trading is not necessarily the same instant as final resolution or redemption. A disputed outcome can tie up capital. Price changes around a dispute may reflect interpretation or liquidity rather than new information about the event itself.

You can model an early sale using the expected executable exit price, not simply the chart’s last print. Selling 100 shares bought at 40¢ for 65¢ yields $25 before entry and exit costs. If no buyer is available at 65¢, that scenario is not immediately executable.

Holding to settlement exchanges liquidity and time for the final outcome. Size a position around the amount you can lose and the capital you may need elsewhere. Our withdrawal guide separates open positions, available balance and transfers.

Start with the official market rules, then compare independent evidence with the price and available depth. A wallet tracker can provide context but cannot prove why a trader bought. An API can provide data but does not turn a correlation into an executable strategy.

Compare Polymarket tools by workflow, or use the tool finder. For a practical sequence from choosing a venue to recording a trade, read the getting-started guide.