A liquidity pool is a smart contract holding reserves of two or more tokens, enabling decentralised trading, lending, and other financial services without traditional market makers or order books. Users who deposit tokens into a liquidity pool become liquidity providers (LPs) and receive LP tokens representing their proportional share. In exchange for providing liquidity, LPs earn a share of the trading fees generated by the pool. Liquidity pools are the foundational primitive of DeFi: without them, decentralised exchanges like Uniswap, Curve, and Raydium could not function. Pool sizes directly affect trading experience: deeper pools mean lower slippage for traders; shallow pools cause significant price impact. Liquidity pools are also used in lending (Aave asset pools), options (Lyra liquidity pools), and insurance (Nexus Mutual capital pool). Creating a liquidity pool requires depositing equal value of both tokens at the current price ratio. When the ratio shifts due to trading, LPs are exposed to impermanent loss. Liquidity mining – rewarding LPs with additional governance tokens – dramatically increased DeFi liquidity from 2020 onwards, catalysing DeFi Summer.
Example: Example: Uniswap v3 ETH/USDC 0.05% fee pool holds $200M in liquidity. A trader swapping $100,000 USDC for ETH experiences only 0.05% slippage. LPs in this pool earn 0.05% of every swap, collectively earning ~$50,000 daily on $10M in daily volume. Deep liquidity enables CEX-competitive DeFi trading.
Learn more: Uniswap v3 – Liquidity
