Miles SinclairBy Miles Sinclair

Updated November 2026

To repair a kitchen faucet, you need to find the source of the problem, shut off the water, and replace the worn part causing the leak, drip or weak flow. Most repairs take under an hour and need only a few basic tools. This guide walks through diagnosis, the core repair steps and how to test your work.

Identify the Problem Before You Start

Start by figuring out what the faucet is doing wrong. A drip from the spout usually points to a worn cartridge, valve seat or washer. Leaking at the base of the handle often means a failed O-ring or packing nut. Low pressure can come from clogged aerators or debris in the cartridge. Check the faucet brand and model, since parts are rarely interchangeable between manufacturers. Many owners find the model number stamped under the sink or on the faucet body.

Shopping for one? See our guide: 7 Best Delta Kitchen Faucet Parts (2026): Repair-Ready Picks.

Shut Off Water and Remove the Handle

Close the under-sink shutoff valves, then open the faucet to drain the remaining water. Place a towel in the sink basin to protect the finish and catch small screws.

  1. Pry off the decorative cap on the handle with a flat blade or a fingernail.
  2. Remove the handle screw with the correct Allen wrench or Phillips screwdriver.
  3. Lift the handle straight up. Some models need a gentle twist.
  4. Unscrew the retaining nut or cap to expose the cartridge or valve body.

Replace the Cartridge or Washers

Pull out the cartridge using its stem or the retaining clip. Compare it to the new part before installing anything, because cartridge sizes vary by manufacturer and model. Seat the new cartridge with its alignment tab facing the correct direction, and reinstall the retaining clip or nut. For compression faucets with rubber washers, replace the washer and the seat if it looks pitted.

Check O-Rings and Seals

Before reassembly, inspect the O-rings around the cartridge and the base of the spout. Flattened, cracked or hardened rings allow water to seep past the stem. Coat new O-rings lightly with silicone plumber’s grease so they seat without tearing.

Reassemble, Restore Water and Test

Reverse the disassembly steps, tightening screws snugly without forcing them. Open the shutoff valves slowly, then run the faucet on hot and cold for a minute to clear air and debris. Check for leaks at the base, the spout and under the sink. Unscrew the aerator and flush it if the flow still seems weak.

Common Mistakes to Avoid

  • Forcing the cartridge in the wrong orientation, which can crack the body.
  • Overtightening the retaining nut, which damages the threads and O-rings.
  • Skipping the shutoff step and getting soaked by residual pressure.
  • Buying parts without matching the brand and model.
  • Using petroleum-based lubricant on rubber parts, which causes swelling.
  • Silicone plumber’s grease keeps O-rings supple and helps them seal without tearing. View on Amazon
  • Faucet repair tool set includes the Allen keys and cartridge puller needed for most handles. View on Amazon
  • Replacement cartridge matched to your model is the most common fix for drips and stiff handles. View on Amazon

FAQ

How long does it take to repair a kitchen faucet?

Most single-handle repairs take 30 to 60 minutes once you have the correct part. Your first attempt may run longer while you learn the disassembly sequence.

Do I need to replace the whole faucet?

Usually not. Cartridges, O-rings and aerators are inexpensive wear items, and replacing them fixes most leaks and weak flow. Consider a new faucet only if the body is cracked or the finish is failing.

When should I call a plumber?

Call a licensed plumber if the leak comes from the supply lines, the shutoff valves won’t close, or you find corrosion inside the sink base. Water damage to cabinets can be costly, so a professional assessment is worth it in those cases.

Conclusion

Repairing a kitchen faucet comes down to diagnosing the leak, shutting off the water and replacing the worn cartridge, washer or O-ring. Match parts to your exact brand and model, and reassemble without overtightening. With those steps, most drips and weak flows can be fixed in a single afternoon.

Ready to choose one?

Miles Sinclair

About Miles Sinclair

Miles Sinclair is part of our editorial team and reviews and edits our kitchen faucets & sinks guides, checking product details against manufacturer specifications and owner feedback.