Sink faucet keeps dripping (drip continues when handle is off)

Use only checks that match the exact appliance or system and its official guide.

1. Check 1

   Dry the spout, handle, faucet base, supply tubes, and cabinet floor, then observe the first place that becomes wet while the handle remains off.

   Expected result: Water returns at the spout tip, around the handle or base, at a supply fitting under the sink, or nowhere after the area is dried.

   Next step: Follow the branch that matches the highest wet point. If water is near electrical equipment or the leak is spreading, contain it and arrange plumbing service before further testing.

   Why this matters

   Why: A spout drip points toward the valve, cartridge, washer, or aerator; handle or base moisture suggests a body seal or handle mechanism; under-sink moisture points toward a supply or connection leak rather than the shutoff valve inside the faucet.

2. Check 2

   Close the handle fully and watch the spout from a dry position long enough to determine whether the drip stops after a short interval or continues repeatedly; do not hold the handle against its stop.

   Expected result: The drip stops after a brief period, or it continues steadily for hours or returns continuously after shutoff.

   Next step: For a brief drip, inspect or clean the aerator as the model instructions allow. For a continuous drip, identify the faucet model and handle style and plan a cartridge or valve diagnosis rather than repeatedly cycling the handle.

   Why this matters

   Why: A brief drip is consistent with residual water or debris at the aerator. Kohler describes a continuous all-day drip after shutoff as characteristic of a worn valve or cartridge.

3. Check 3

   Inspect the removable screen at the spout end for visible mineral or debris buildup and clean it only by the faucet manufacturer's instructions; do not force a seized aerator or scratch the finish.

   Expected result: The screen is obstructed and the drip is brief, the screen is clear, or cleaning does not change a continuous drip.

   Next step: Reinstall the aerator only when its parts are intact and the model instructions permit. If the drip continues all day, move to model identification and service rather than treating the aerator as the root cause.

   Why this matters

   Why: Aerator debris can hold water and prolong a short post-shutoff drip, but a continuous drip is more consistent with the valve or cartridge under the handle.

4. Check 4

   Record whether the sink faucet has one handle or two and locate its model information from an accessible label or the owner's paperwork; do not remove the handle or cartridge just to identify it.

   Expected result: The faucet is single-handle, two-handle, or the model cannot be confirmed.

   Next step: Use the model-specific parts diagram or give the recorded identity to a plumber. If the model cannot be found and the drip is continuous, arrange diagnosis instead of ordering by appearance.

   Why this matters

   Why: Single- and two-handle faucets can use different valve or cartridge arrangements, and manufacturers state that replacement parts vary by model. An unconfirmed model makes a guessed cartridge or washer unreliable.

5. Check 5

   With a towel below the plumbing, look at the hot and cold supply fittings, flexible tubes, and stop valves without loosening them; do not reach through a puddle or force a corroded valve.

   Expected result: The supply connection is wet, a stop valve is corroded or seized, water appears only when the faucet is used, or the connections stay dry while the spout drips.

   Next step: If a stop valve turns normally, close it gently to contain a growing leak and arrange service. If it is seized, corroded, or the leak persists at a fitting, stop and call a plumber; do not force or disassemble the connection.

   Why this matters

   Why: A wet fitting or valve is a surface leak that can be mistaken for a faucet cartridge leak. Dry connections with a continuous spout drip keep the internal valve or cartridge as the leading path.

6. Check 6

   After cleaning and visible checks, observe whether the faucet still drips with the handle fully off or whether water is spreading into the cabinet, wall, or electrical area; do not open the faucet body while the water supply is pressurized.

   Expected result: The drip stops, the spout continues to drip continuously, water leaks around the handle or base, a supply connection leaks, or water is approaching electrical equipment.

   Next step: Contain the water, close accessible stop valves only if they turn safely, and arrange qualified plumbing service. If the area is wet around electrical equipment, keep clear and have the electrical hazard assessed before touching anything.

   Why this matters

   Why: A persistent drip or body and supply leak requires a model-specific seal, cartridge, valve, or connection repair. Water near electrical equipment adds a property and shock hazard beyond routine faucet maintenance.