> ## Documentation Index > Fetch the complete documentation index at: https://polymarketus.mintlify.site/llms.txt > Use this file to discover all available pages before exploring further. # Spread > Learn how the gap between bid and ask affects your execution price Every market has two prices: * The **bid** is the highest price buyers are willing to pay * The **ask** is the lowest price sellers are willing to accept The **spread** is the gap between these two prices. A wider gap means you may pay more when buying or receive less when selling. *** ## How It Works 1. When you buy, you pay the **ask** price. 2. When you sell, you receive the **bid** price. 3. The difference between them is the **spread**. 4. Tighter spreads mean better execution. 5. Wider spreads mean higher trading cost. *** ## Examples ### Tight Spread A tight spread means the bid and ask are close together, common in more liquid markets. Order book showing a tight spread with bid and ask close together. ### Wide Spread A wide spread means the bid and ask are far apart, common in less liquid markets. Order book screenshot showing a wide gap between bid and ask. *** ## Key Points * You buy at the **ask** and sell at the **bid** * The spread is the gap between these two prices * Wider spreads increase your trading cost * More liquid markets usually have tighter spreads * Your execution price depends on the bid, the ask, and the available size