How to Turn Off Water to Sink

How to Turn Off Water to a Sink

Whether you're replacing a faucet, fixing a leak, or dealing with a plumbing emergency, knowing how to turn off the water to a sink is essential. Here's how to do it quickly and correctly.

Step 1: Find the Shut-Off Valves

Every sink has two shut-off valves — one for hot water and one for cold water. They're located under the sink, on the supply lines that connect the wall to the faucet.

Open the cabinet under the sink and look for two valves on the pipes coming out of the wall or floor. They typically look like:

• Oval or football-shaped handles — most common
• Round wheel handles — older gate valve style
• Lever handles — ball valve style

Step 2: Turn Off the Valves

• Oval/round handle: Turn clockwise until it stops
• Lever handle: Turn 90° so the lever is perpendicular to the supply line

Turn both the hot and cold valves. For most repairs, you need both off. For a hot-water-only repair (like replacing a hot water supply line), you only need to close the hot valve.

Step 3: Confirm the Water Is Off

Turn on the faucet. Water should stop flowing within a few seconds as the remaining water in the line drains out. If water keeps flowing, the valve isn't fully closed — turn it further clockwise.

What If the Valves Are Stuck?

Old shut-off valves can seize from years of non-use:

• Apply penetrating oil to the valve stem and wait a few minutes
• Try again with gentle steady pressure — don't force it
• If the valve won't close, turn off the main house water supply
• Replace stuck valves when you have the chance — they're useless in an emergency

Use a rubber strap wrench for extra grip on stubborn valves without damaging the finish.

What If There Are No Valves?

Some older homes don't have individual sink shut-off valves. Options:

• Turn off the main house water supply
• Have shut-off valves installed — a plumber can add them in under an hour

After the Repair: Turn Water Back On

1. Make sure the faucet is in the off position before turning the valves back on
2. Turn the valves counterclockwise slowly
3. Check all connections under the sink for leaks
4. Turn the faucet on and off to test

Quick Reference: Which Valve to Close

Bottom Line

The sink shut-off valves are under the sink on the supply lines. Turn them clockwise to close. Test by turning on the faucet — water should stop. If valves are stuck, use the main house shut-off and replace the stuck valves when you can.