Plumbing · checked 5 Oct 2026
Kitchen sink leaking under the cabinet
Safety first
- Stop using the sink, dishwasher, and disposal.
- Stay clear of wet outlets, plugs, cords, and disposal.
- If electrically safe, gently close both sink water shutoff valves.
Fix it nowEight steps
- Keep clear if electrical parts are wet; call an electrician before touching anything.Wet powered equipment can electrocute you.
- Close both sink shutoffs clockwise gently; never force a stuck valve.This isolates the faucet's hot and cold supplies.
- If spraying continues, close your accessible home water shutoff; call a plumber now.Sink shutoffs may not isolate the leaking supply section.
The other five steps
- Once electrically safe, place a bucket beneath the drip; dry accessible pipes.Catch water and make fresh drips easier to locate.
- Inspect with a flashlight; identify the highest wet connection without moving hoses.Supply hoses, valves, and faucet connections require different repairs.
- Hand-snug only an obviously loose plastic drain nut; stop at resistance.Overtightening can crack plastic; slip joints seal with washers.
- For drain-only leaks, pour one cup into the empty sink; watch underneath.A small test checks the joint without reopening supply valves.
- If dry, reopen valves slowly; test briefly. If leaking, shut off; call plumber.Verify the repair before normal use; persistent leaks need attention.
When to stop
Stop and get a plumber if:
- Water reaches an outlet, plug, cord, or disposal: keep clear; call an electrician.
- Water sprays continuously, or shutoffs will not close: call a plumber now.
- A supply hose, valve, or faucet connection leaks: leave water off; call a plumber.
- Pipes are cracked, badly corroded, or leaking inside the wall: call a plumber.
- The drain still leaks after gentle hand-tightening: stop using it; call a plumber.
What it probably is
Loose drain joint or worn washerThe U-shaped drain joint drips when water drains.You can check
Leaking water-supply hose or connectionA thin supply hose stays wet even with the faucet off.For a pro
Leaking shutoff valveWater beads around the valve handle with the faucet off.For a pro
Leaking faucet hoseWater comes from a faucet hose or connector during faucet use.For a pro
Time and parts
- Time
- About 10–20 minutes for inspection and one loose drain nut; drying takes longer.
- Parts
- $0 for hand-tightening; no replacement parts included.
Fair price, if a pro does itUnited States
$124–370per job
Get it done
More than a quick fix? Vora gets quotes privately and recommends one plumber.
The plumbers we’d call in Tyler & Longview · Leak: what to do
Checked against
- CPSC: Dangers with wet appliances
- Moen: Kitchen faucet leaking under the sink (Spanish)
- Moen: Leaks around supply hoses and shutoff valves
- Oatey: How to install and leak-test a P-trap
Written for Vora from these public sources and checked on 5 Oct 2026. General guidance, not a substitute for a pro on site. In danger, leave and call 911.