How to Read Yes/No Prices on Polymarket (US 2026)

Official Prices & Market Data: every contract is priced between $0 and $1, and that price is the market’s collective belief about how likely the outcome is. Their teaching table: $0.25 is roughly a 25% chance, $0.50 is a coin flip, $0.75 is a 75% chance. Official What is Polymarket US uses the same map — 62¢ means roughly a 62% chance the event occurs. A teaching Yes at 40¢ is the same idea: the book is implying about 40%. We do not reprint a live 40¢ ticket.

Official Odds Display: tap the Odds control at the top right and switch between price (¢) and percent chance (%). Their teaching pair is the same market shown two ways — “only the way it’s shown changes.” A 40¢ Yes and a 40% Yes are one reading, not two different odds. We will not invent a third American-odds column those US pages do not print.

Official Market Settlement and Official Prices & Market Data: a winning contract settles at $1.00 and a losing contract at $0.00. Official What is Polymarket US teaching fill: buy Yes at 55¢, event happens, settle $1.00, +45¢ per contract on that example; event does not happen, settle $0.00, you lose the 55¢. That is the published settlement math before any trading fee. We will not invent a net-of-fee payout, and we will not quote tonight’s book.

Sportsbook moneylines are a house price you take or leave, often written as +150 or −135. A Polymarket Yes at 0.40 is a traded event-contract price other users posted. Official How are Polymarket odds determined?: Polymarket US does not set prices or take the other side. Official What is Polymarket US: your order matches another user’s order on a central limit order book. Do not convert 40¢ into an American moneyline and treat that conversion as the ticket. We will not publish that table.

Official Place a Trade: tap Yes if you think the printed event happens, or No if you think it does not. Official Browse Markets: each market shows the question, the Yes and No prices, and a resolution date. A 40¢ Yes is “this sentence happens.” It is not automatically the opponent’s moneyline, and it is not a push unless that ticket’s rules say so. The contract how-to is the sentence. This page is the number on that sentence.

Official What is Polymarket US: unlike a sportsbook, you can sell the contract before the event resolves, and the odds come from real trades as traders adjust orders. That is why a 40¢ print can move after you look at it. It is also why a headline 40¢ is not a locked sportsbook hold. See prediction markets vs sportsbooks if you wanted a house line. That is a different product.

Official Browse Markets shows current Yes and No prices on the tile. Official Prices & Market Data: a market order fills at the best available price on the other side right now — the BBO. Official Spreads: you buy at the ask and sell at the bid. If the tile says 40¢ and the best ask is higher, the ask is what a take-now buy pays. We do not reprint a live tile or a live ask.

Official US market-book stats name lastTradePx (and lastTradeQty): the price and quantity of the most recent trade. Official Place a Trade and Official Odds Display do not reprint a retail column header literally labelled “Last” on the swipe we checked. We will not invent one. The action is the same: the most recent match is history. Size can be pulled or added after that print. Official How are Polymarket odds determined?: prices update whenever a buy or sell is matched.

Public international help (“How Are Prices Calculated?”) says the displayed probability is the midpoint of the bid-ask spread, unless that spread is over $0.10, in which case the last traded price is used. Their teaching example: 37% as the midpoint of a 34¢ bid and a 40¢ ask. We could not confirm that $0.10 switch, or a retail “midpoint” label, on the US docs we checked. We will not paste it onto the US app as a rule. If the headline and the BBO disagree, trust the book in front of you.

Official Odds Display’s teaching pair is WAS 17¢ / KC 86¢ (or 17% / 86%). Those two printed numbers add to 103¢, not a clean $1.00. That is a docs example — not tonight’s board, and not a promise every Yes + No tile sums to 100. Last prints on each side can come from different matches at different times. Do not treat “100 minus the Yes” as the No you will actually pay.

Official Spreads: when you buy, you pay the ask; when you sell, you receive the bid; the gap is the spread. Buying Yes at the Yes ask and buying No at the No ask is two crosses. Those two asks can add to more than $1 even when the two last prints look like complements. Official Prices & Market Data: a tight spread means the market is liquid; a wide spread means fewer people are trading. We do not reprint a live pair.

Official Glossary: fees are trading or platform fees applied to executed orders. Official US Fee Schedule publishes that charge on its own page. A Yes you buy at 40¢ plus a No you buy at 60¢ is not a locked $1 after the exchange line item, and it is not an arb we will write up. We will not invent a payout formula or paste a theta table onto this price read. The published cost stack is How Polymarket fees work — this page does not clone it.

Public international help (“What is Polymarket”) describes Yes + No pairs as collateralized at $1.00 USDC when complementary orders match. Polymarket US is the fiat, CFTC-regulated desk — Official What is Polymarket US says trades are in US dollars, not that crypto product. We will not mash the international USDC pairing onto a US tile as if those US pages printed it. Settlement on Official Market Settlement is still $1.00 or $0.00 on the side you hold.

Official Prices & Market Data: the BBO is the price a market order would trade at if size is there. Official Glossary: size is contracts available at a price. If the best ask is a thin clip, a take-now buy can walk. How to read the Polymarket order book is that ladder — this page does not repeat the teaching fills. Glance at the book. Then decide.

Official How are Polymarket odds determined?: odds move when orders match. Official Spreads: your execution price depends on the bid, the ask, and the available size. A 40¢ last match does not cap the next ask. Official Liquidity (on the order-book how-to) treats the displayed price as dynamic, especially in live sports. We do not reprint a live last print.

Official What is Polymarket US teaching profit (+45¢ on a 55¢ Yes that settles $1.00) is settlement math on a docs example. It is not a live NFL price, not a sportsbook ticket, and not net of the taker fee. The first swipe lives on How to buy your first NFL ticket. The printed sports number lives on How to read a spread or total. We link those instead of cloning them.