Fix Low Water Pressure in Your Kitchen Sink

Low water pressure at the kitchen sink is one of those small annoyances that becomes unbearable fast. You can't rinse dishes efficiently, fill pots take forever, and suddenly you're questioning why your kitchen feels broken. The good news: this is almost always fixable without calling a plumber. The culprit is usually sitting right at the tip of your faucet—the aerator, a small screen that mixes air into the water stream. Mineral deposits and debris get trapped there and restrict flow. Sometimes the problem lives deeper in the supply lines, but you'll diagnose that as you go. This guide walks you through the most common fixes in order of likelihood, starting with the easiest.

1. Expose the Aerator. Locate the aerator at the tip of your faucet spout—it's the small cylindrical piece where water comes out. Look underneath or around the rim for a flat edge or groove. Use an adjustable wrench or pliers wrapped in a cloth to grip it firmly and turn counterclockwise. If it's tight, apply steady pressure rather than force. Once loose, unscrew it by hand the rest of the way. Set the small parts on a paper towel in order so you can reassemble them correctly.
2. Spot the Culprit. Look at all the pieces you removed: the outer cage, the internal screens, the flow restrictor disc, and any gaskets. Mineral buildup appears as white or tan crusty deposits. Debris looks like sand or sediment. Hold each screen up to light—you're looking for blockages. Even a small amount of mineral crust can choke flow to a trickle.
3. Dissolve Mineral Buildup. Fill a small cup or glass with white vinegar and submerge all the aerator parts except rubber gaskets. Let them soak for 15 to 30 minutes. The acidity dissolves mineral deposits. For stubborn buildup, extend the soak to an hour or overnight. Don't soak rubber washers for more than 30 minutes—vinegar can degrade them.
4. Scrub Away Deposits. Remove the parts from the vinegar and use an old toothbrush or soft brass brush to scrub away loosened mineral deposits. Pay special attention to the mesh screens—that's where buildup concentrates. Work from inside and outside the screens. Rinse everything under warm tap water. If mineral is stubborn, return the part to vinegar for another 10 minutes and scrub again.
5. Check Inside Spout. While the aerator is off, turn on the sink and let water run for a few seconds into the sink. Observe the stream—if it sprays unevenly or flows weakly even without the aerator, debris is inside the spout. Use a small flashlight to look up into the opening. If you see sediment, use a small stiff wire or straightened paper clip to gently dislodge it. Run water again to flush debris away.
6. Stack Parts Precisely. Stack the aerator parts back in the order you removed them, using your photo as reference. The typical order from outside to inside is: outer cage, washer, screen, flow restrictor, fine mesh screen, and final washer. Tighten by hand only—you don't need a wrench here. Hand-tight is correct. Over-tightening can crack the screens or crush gaskets.
7. Reinstall the Aerator. Line up the aerator threads with the spout threads and turn clockwise by hand. Once you feel resistance, use the wrench to tighten just enough to seal. The aerator should sit flush with the spout—no gaps. Don't over-tighten, which is a common mistake. Snug is enough.
8. Verify Pressure Restored. Turn on cold water first and observe the flow and spray pattern. It should come out in a full, even cone without weak spots. Let it run for 10 seconds. Then switch to hot water and repeat. If both sides are strong and even, you've solved it. If one side is still weak, the problem is upstream in that supply line.
9. Open Shut-Off Valves. Open the cabinet under the sink. You'll see two flexible lines coming from the wall or floor, each with a small valve knob. One is hot, one is cold. Make sure both valves are turned fully counterclockwise (open). If either valve is partially closed, it restricts flow to that side. Turn it fully open. This is the most common culprit after a clogged aerator.
10. Straighten Any Kinks. Look at the flexible hoses connecting the shut-off valves to the faucet. They should run straight or in gentle curves—no sharp bends, twists, or compression. If you see a kink or the line feels hard or pinched, that's your restriction. Gently straighten the line. If the line is old and cracked or permanently kinked, it needs replacement.
11. Swap Out Old Lines. If the line is kinked and won't straighten, cracked, or more than 10 years old, replace it. Turn off both shut-off valves, unscrew the old line from the valve and faucet connection, and take it to the hardware store to match the length and thread size. Install the new line by hand-tightening at both ends, then snug one quarter turn with a wrench. Don't over-tighten.
12. Check House-Wide Pressure. If both sink sides are slow and the aerator is clean, check your whole-house water pressure. Locate the main shut-off valve where water enters your home (usually near the meter in the basement, crawlspace, or under the house). If the valve is partially closed, it starves the whole house. Turn it fully counterclockwise (open). This is rare but worth checking before you assume a line issue.