What Is a Faucet Cartridge?
Quick answer
The replaceable insides of a faucet. When it drips, you swap this $10–$20 part, not the whole faucet.
The replaceable valve unit inside most modern faucets, a plastic-and-brass cylinder that controls flow and temperature as the handle moves. When a faucet drips, the cartridge's internal seals are worn; swapping the cartridge ($10–$20, brand-specific) is the standard fix, and the faucet body itself almost never needs replacing.
Fixes that use this
Kitchen
How to Fix a Leaky Faucet (Find the Right Part First)
A dripping faucet is a worn cartridge, washer, or seal. How to identify your faucet type, buy the right $5–$20 part, and swap it in under an hour.
Time30–60 min Cost$5–$20 moderate