What Is Providing Liquidity?
Providing liquidity means depositing two tokens into a decentralized exchange pool so others can trade against them, and earning a share of trading fees in return. Returns must be weighed against price moves and impermanent loss.
On this page 10
- How does a liquidity pool work?
- What do you own when you deposit into a pool?
- How is fee income calculated? A worked example
- Why do trades change your balance?
- What does choosing a price range mean?
- Which pools carry less risk?
- How to add liquidity, step by step
- How do you know if you’re making money?
- Risks of providing liquidity
- Sources
Providing liquidity means depositing two tokens into a liquidity pool on a decentralized exchange (DEX) so that other users can trade against them, and earning a share of the trading fees in return. Anyone who deposits is a liquidity provider, or LP. Uniswap, Curve and PancakeSwap all work this way: instead of a professional market maker on the other side of each trade, there’s a pool of tokens supplied by users.
It can look like passive income, but it’s really an active market position. The token amounts you hold in the pool change with every trade, so your result has to be judged not just by fee income, but against what would have happened if you’d simply held the tokens.
How does a liquidity pool work?
In a classic pool, two tokens such as ETH and USDC are deposited in equal value. The pool’s price comes from the ratio between them. When someone pays USDC into the pool to take ETH out, the pool holds less ETH and more USDC, so ETH’s price in the pool rises. Arbitrage bots quickly close any gap with prices elsewhere.
Uniswap v2 links the two balances with a “constant product” formula: the product of the two token amounts stays constant after each trade, excluding fees. This lets the pool quote a price at any level.
What do you own when you deposit into a pool?
When you add liquidity, you receive a claim on your share of the pool. In classic pools like Uniswap v2, this is an ERC-20 token called an LP token. In pools where you choose a price range, like Uniswap v3, each position has its own settings, so your share is represented by an NFT.
That LP token or NFT is the only key to withdrawing your share. Sending it elsewhere or losing it means sending or losing the position itself. Some platforms let you stake LP tokens in another contract for extra rewards, which adds another layer of contract risk.
How is fee income calculated? A worked example
Take a hypothetical pool holding 10 ETH and 20,000 USDC. You add 1 ETH and 2,000 USDC, bringing it to 11 ETH and 22,000 USDC, so your share is about 9.09%. If the pool charges 0.3% and sees $100,000 of trading in a day, it generates $300 in fees, and roughly $27 of that is yours.
In reality, fee income varies daily with trading volume, total liquidity and your share. The annual percentage rate (APR) shown in apps is usually extrapolated from the last few days’ volume and is not a promise of future income.
Why do trades change your balance?
Your percentage share may stay the same, but the token amounts inside it keep changing. When ETH rises, buyers take ETH out of the pool and leave USDC behind, so your share holds less ETH and more USDC. When ETH falls, the reverse happens and you accumulate more ETH.
The net effect is that you end up holding less of the token that went up and more of the one that went down. The gap versus simply holding both tokens in your wallet is called impermanent loss. Fees may or may not make up for it.
What does choosing a price range mean?
With concentrated liquidity, popularized by Uniswap v3, your liquidity is only used within a price range you choose. If you set a range of $2,500–$3,500 for ETH, for example, the same capital earns far more fees while the price stays inside that band.
Once the price leaves your range, your position converts entirely into one token and stops earning fees. If the price moves above the range you’re left fully in USDC; below it, fully in ETH. A narrow range means more fees, but also more active management and greater impermanent loss.
Which pools carry less risk?
A pool’s risk depends largely on how closely its two tokens move together:
- Stablecoin pairs (e.g. USDC/USDT): both tokens sit near $1, so impermanent loss is minimal. Fee rates tend to be low too, and the main risk is one stablecoin losing its peg.
- Correlated pairs (e.g. ETH and a liquid staking token): prices track each other closely, so the risk is moderate.
- Uncorrelated pairs (e.g. ETH/USDC, or a small altcoin against ETH): fee income can be high, but impermanent loss grows quickly as the price ratio shifts.
How to add liquidity, step by step
- Go to the DEX’s official site and connect your wallet on the right network.
- Pick the pool: verify both tokens by contract address and choose the fee tier.
- Set a price range if the pool requires one; the app will calculate how much of each token to deposit.
- Approve both tokens for spending, ideally only for the amounts you’re depositing.
- Sign the add-liquidity transaction and check that the LP token or position NFT has arrived in your wallet.
How do you know if you’re making money?
Compare three figures: the current value of the tokens you could withdraw, the fees you’ve earned, and what the original tokens would be worth today if you’d just held them. Don’t forget the gas you paid to approve, add and remove liquidity; on small positions those costs can eat a large share of the gains.
Risks of providing liquidity
- Impermanent loss: falling behind a simple hold as the price ratio between the tokens changes.
- Smart contract risk: a bug in the pool or rewards contract.
- Token risk: if one token in the pair collapses, the pool fills up with the worthless token.
- Misleading yields: a high APR built on temporary volume or reward tokens whose price may fall.
Pool size (TVL) is no guarantee of safety; it only shows how much money has been deposited.