Uniswap Launches Dynamic Fees for Two Stable-Pair Pools

Uniswap Labs has deployed StablePair Hook, a Uniswap v4 feature that applies variable liquidity-provider fees to two stable-pair pools on Ethereum rather than using a single fixed rate. The initial deployments pair USDC with USDT and USDC with USDG. The new fee model is intended to alter how revenue is split between liquidity providers and arbitrageurs when a pool's price departs from an expected reference rate.

Each StablePair-configured pool includes a reference rate and a narrow price band around it. The hook determines the LP fee from three inputs: the pool's current price, how far that price sits from the reference rate, and the direction of the proposed swap. When the pool price remains inside the band, the fee adapts to produce consistent pre-price-impact buy and sell quotes; at the reference rate both trade directions pay the configured band width.

Fees change as the pool approaches band edges: a trade that moves the price toward an edge sees its fee decline toward zero, while a trade in the opposite direction faces a higher fee that can approach roughly twice the band width. If a trade would push the pool further outside the band, it pays no fee because it does not correct the mispricing. Corrective trades that bring the pool back toward the reference rate are offered at a starting fee set at the band's far edge and that fee decays once per block until someone executes it; the pool collects whatever fee is paid at execution.

Uniswap notes that the StablePair mechanism does not remove price impact: fees are independent of swap size and a sufficiently large swap can still move along the pool's pricing curve and receive a worse average execution price than a smaller trade. The StablePair rollout is currently limited to the two Ethereum pools created by Uniswap Labs against the hook, and pool parameters and fee logic can be modified later through Uniswap governance without requiring liquidity to migrate to a new pool.