These are the most common signs your faucet needs replacing: 1 - Rust: It’s time to replace your faucet if you spot any amount of rust around the base. Rust will start with a slow leak but will gradually get worse and potentially have a devastating impact on your faucet. 2 - Mineral deposit buildup: Mineral deposits happen because of the “hard water” (water with a higher mineral content) passing through your faucet. If left unchecked, the mineral buildup could lead to significant damage to the faucet fixture, including the finish, flanges, gaskets, metal, and filters. 3 - Leaks and mold: Now, not all faucet leaks call for replacement, in most cases, a simple repair would do. However, if you have a leak that goes unnoticed, it will contribute to mold accumulation/ growth, and rust.