General information, not financial, investment, legal, tax or betting advice · Prediction markets carry risk of loss · 18+ or the legal age in your region
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GlossaryPlain definitions

Bid

A bid is an order to buy a contract at a stated price, and the best bid is the highest price buyers are currently willing to pay.

By Fredrik FilipssonFounder and editor · Two decades in advisory, hospitality and mediaEditorial review by Morten Andersen · Last reviewed 12 December 2025

Last reviewed 12 December 2025 · Educational, not advice

Information, not advice. This page is general information, not financial, investment, legal, tax, or betting advice. Prediction markets carry a real risk of loss. You must be 18+ or the legal age in your region.
In plain terms

What it means.

A bid is the buy side of an order. When you place a bid you are saying you are willing to buy a contract at a particular price, and that order sits in the order book until someone is willing to sell to you at that level or you cancel it. The best bid is the highest price anyone is currently offering to pay, and it is one of the two numbers, alongside the best ask, that define what a market looks like at any moment. In short, the bid is what buyers will pay, while the ask is what sellers will accept.

The gap between the best bid and the best ask is the spread, and it tells you something about the cost of trading. To buy immediately you usually pay the ask, and to sell immediately you usually take the bid, so the spread is a real cost you cross when you trade at market. A tight gap between bid and ask points to an active, competitive market, while a wide gap suggests a thin one where trading is more expensive and harder to do in size.

A bid is more than a single price, because behind it sits size. The order book shows not only the best bid but the amount buyers want at that price and the bids stacked below it. This is the market's depth on the buy side. If you want to sell more than the best bid can absorb, your order fills the top bid and then steps down to lower bids, so your average sale price can be worse than the best bid you first saw. Reading the size behind a bid is as important as reading the price.

You interact with the bid in two ways. If you want to sell now, you can hit the best bid and trade against a waiting buyer, accepting their price for certainty of filling. If you want to buy but not at the current ask, you can post your own bid below the market and wait for a seller to come to you, which can lower your cost but gives up certainty that the trade happens at all. Which approach suits you depends on whether you value price or speed, and on how liquid the market is.

A worked example

Suppose a contract shows a best bid of forty seven cents with one hundred contracts wanted there, and a best ask of fifty cents. If you want to sell now, you can hit the bid and sell at forty seven. If you would rather buy below the ask, you might post your own bid at forty five and wait. You only trade if a seller is willing to meet you there, so your better price comes with the risk that the order never fills.

Illustrative only. Numbers are examples, not a quote or a prediction, and exclude fees.

A note on risk,

Reading the bid tells you what buyers will pay, not whether a trade is wise or an outcome likely. A tight spread does not make a position safe. Prediction markets can lose you money. Stake only what you can afford to lose, never to chase a loss, and never on borrowed money. If it stops feeling like a free choice, step back. In the United States you can call or text the helpline on 1-800-GAMBLER or visit ncpgambling.org.

Common questions

Answered plainly.

What is a bid in a prediction market?

It is an order to buy a contract at a stated price. The best bid is the highest price buyers are currently willing to pay, and it sits in the order book until a seller meets it or the order is cancelled. It is the buy side counterpart to the ask.

What is the difference between the bid and the ask?

The bid is the highest price buyers will pay, and the ask is the lowest price sellers will accept. The gap between them is the spread, a real cost you cross when you trade at market, since you usually buy at the ask and sell at the bid.

What happens if I sell more than the best bid can take?

Your order fills against the best bid first, then steps down to lower bids in the book, so your average sale price can be worse than the best bid you saw. The size resting behind a bid, its depth, decides how far your order walks down.

Does the bid tell me whether to trade?

No. A bid only shows what buyers will currently pay and how much size is there. It says nothing about whether an outcome is likely or a price is fair, and we never name a contract to trade. It helps you judge the cost and feasibility of trading, not the merits of a position.

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