What is Limit Order?
How it works
A limit order is placed on an order book, either on a centralized exchange (CEX) or a decentralized exchange (DEX) that supports order books, such as dYdX or Serum. The user specifies a price (e.g., buy ETH at $3,000) and an amount. The order remains open until it is filled, cancelled, or expires. When the market price reaches the limit price, the order executes as a maker order, adding liquidity to the book and often paying lower fees than market orders. On DEXs like 0x, limit orders are off-chain signed messages posted to relayers; when a taker matches them, the trade settles on-chain via smart contracts.
Partial fills are possible: if only a portion of the order is matched at the limit price, the remainder stays active. Limit orders can be set with a time-in-force parameter (e.g., Good-Til-Cancelled or Immediate-or-Cancel). Some protocols, such as Uniswap X (now Uniswap Interface with limit orders), use intents and a fillers network to execute limit orders by comparing quotes across liquidity sources. In order-book AMM hybrids like Trader Joe's Liquidity Book, limit orders can be placed within specific price intervals, earning fees while waiting for execution.
Why it matters
Limit orders are fundamental for precise trading in crypto markets. They enable users to set entry or exit points without constant screen watching, reducing emotional decisions and minimizing slippage compared to market orders. In DeFi, limit orders allow passive liquidity provision on order-book DEXs, letting traders earn fees (like a maker rebate) while waiting. They also underpin advanced strategies like arbitrage and grid trading. By offering price certainty, limit orders make decentralized trading more accessible and competitive with centralized exchanges.
Real-world examples
dYdX, a Layer-2 DEX, supports limit orders with leverage on its perpetuals order book. 0x Protocol enables peer-to-peer limit orders that can be filled by anyone, powering aggregators like Matcha. Uniswap's interface added native limit orders in 2022 using a fillers network. On Solana, Serum and Raydium offer on-chain limit orders, while Ethereum-based Loopring’s zkRollup DEX also supports them.
FAQ
How is a limit order different from a market order?
A market order buys or sells immediately at the current best available price, while a limit order only executes at a specified price or better, which may result in no execution if the market never reaches that price.
Can a limit order be partially filled?
Yes, limit orders on order-book exchanges often allow partial fills; the remaining unfilled quantity stays active until cancelled or fully executed.
What happens if my limit order is not filled?
Your limit order remains open until it expires based on the time-in-force setting (e.g., GTC) or you cancel it. On some DeFi protocols, fees may apply for cancellation.
Related terms
Go deeper
Browse the complete crypto glossary to explore related terms and concepts.
Browse Glossary