How to Find the Right Replacement Part for Your Leaky Faucet (Step-by-Step Guide)

Why you don’t need a whole new faucet

A dripping faucet feels like a small problem, but the wasted water and the constant sound add up fast. The good news is that in most cases you don’t need a brand-new faucet — you just need the right replacement part (usually a cartridge, stem, or seal).

This guide walks you through how to identify your faucet, figure out which part is failing, and match it confidently so you only have to fix it once.

Step 1: Decide if this is a repair you want to tackle

Before you grab tools, do a quick check:

• Where is the leak? Is it dripping from the spout, seeping around the handle, or leaking under the sink?
• Are you comfortable turning off water and removing a handle? Most cartridge swaps are beginner-friendly as long as you can safely shut off the supply.

If you’re okay with light disassembly and can work carefully over the sink, this is usually a solid DIY project.

Step 2: Turn off the water and inspect the faucet

1. Shut off the water supply.
   Look under the sink for the hot and cold shut-off valves. Turn them clockwise until they stop.
2. Relieve pressure.
   Open the faucet to make sure the water is off and to remove pressure in the lines.
3. Note where the leak is.
   • Drip from the spout – usually a cartridge, stem, or internal seals.
   • Leak around the handle – often O-rings or cartridge seals.
   • Leak under the sink – could be supply lines or mounting hardware rather than the cartridge itself.

Step 3: Identify the faucet brand and model

Getting the brand and model right is the fastest way to land on the correct replacement part.

1. Look for a logo.
   Check the base, spout, or handle for a stamped or printed logo (Moen, Delta, Kohler, American Standard, etc.). A phone flashlight helps.
2. Check under the sink.
   Many faucets have a tag or sticker with the model number on the underside of the faucet or attached to the supply lines.
3. Search your records.
   Look in email receipts, home-improvement store accounts, or old manuals if you purchased the faucet yourself.
4. Use photos to visually match.
   If you can’t find a model number, take clear photos from multiple angles (front, side, top, handle close-up) so you can visually compare to product images later.

While you’re at it, make a note of the finish (chrome, brushed nickel, matte black, etc.) in case trim kits or handles are finish-specific.

Step 4: Figure out which part is failing

Once you know the brand/model (or at least have it narrowed down), focus on the specific part:

• Cartridge: Common in single-handle faucets. Controls flow and temperature. Worn cartridges cause drips from the spout or temperature issues.
• Valve stem + washer: Often found in older two-handle faucets. A worn washer or seat on the hot or cold side will cause a drip.
• O-rings and seals: Used around the base of the spout or under the handle. When they flatten or crack, you get leaks around the handle or faucet base.
• Aerator: Screws onto the spout tip. Usually affects flow, not leaking, but can be cleaned or replaced if water is spraying strange directions.

Where you see water is your best clue:

• Drip from spout: cartridge or stem/washer.
• Leak from handle area: O-rings or cartridge seals.
• Leak around the base of the spout: spout O-rings.

Step 5: Disassemble carefully and take reference photos

This is where a few photos will save you a lot of guesswork when reassembling.

1. Protect the sink.
   Place a towel over the drain or use a small tray so screws and small parts can’t disappear.
2. Remove the handle.
   Look for a decorative cap with “H” or “C” or a logo. Gently pry it up, remove the screw underneath, and lift the handle straight off.
3. Photograph each step.
   Take pictures as you remove trim pieces and expose the cartridge or stem. Capture any tabs, clips, or flat spots that determine orientation.
4. Remove the cartridge or stem.
   Some pull straight out; others have a nut or retaining clip. Work slowly so you don’t damage the faucet body.

With the cartridge or stem removed, take close-up photos from multiple angles. These will be critical when you match the new part.

Step 6: Match the replacement part

Now you have everything you need: brand, (ideally) model, and clear photos of the old part.

When comparing parts, pay attention to:

• Overall length and shape of the cartridge or stem.
• Number and position of O-rings or seals.
• Splines, tabs, or flat sides that key into the handle or faucet body.
• Any part numbers or markings printed on the side.

Look for parts labeled as genuine replacements for your brand/model, or for aftermarket parts that specifically list compatibility with your faucet series.

Step 7: Install the new part and test for leaks

1. Clean the valve opening.
   Wipe away mineral buildup or debris where the cartridge or stem sits. A soft cloth or non-scratch pad works well.
2. Install the new part.
   Align tabs or flats using your reference photos. Make sure the cartridge or stem is seated fully before replacing clips or nuts.
3. Reassemble the faucet.
   Reinstall trim and the handle in the same orientation.
4. Turn the water back on slowly.
   Open the shut-off valves, then open and close the faucet a few times to flush air from the lines.
5. Check for leaks.
   Watch the spout, handle area, and faucet base. Let it sit a few minutes to make sure no slow drip returns.

Step 8: Save your “faucet profile” for next time

Once everything is working:

• Save your best faucet photos in a “Home Repairs” album on your phone.
• Write down the brand, model, and part number that fixed the leak.
• Keep the old cartridge in a labeled bag for reference if you ever need to compare again.

The next time something wears out, you’ll be able to order the right part in just a few minutes.

Later on, when your Parts Finder and affiliate links are live, you can come back to this guide and add a short “Recommended replacement parts” section with direct links to compatible cartridges and repair kits.