What to Do If You Have a Water Leak in Your House
Quick answer
If a leak in your house is flowing fast or reaching outlets, treat it as an emergency. Do not touch wet electrical equipment or stand in water, and turn off power only if safe. Shut off the water at the nearest valve, find the source, and dry the area within 24 to 48 hours to prevent mold.
Key takeaways
- Dry water-damaged areas and items within 24 to 48 hours to prevent mold growth (U.S. EPA, A Brief Guide to Mold, Moisture and Your Home).
- Do not touch wet electrical equipment or stand in water to reach it. Turn off the electricity only if it is safe to do so (Ready.gov, Floods).
- EPA's two-hour meter test: take a reading with no water in use, then read again after two hours. A changed reading can mean a leak (U.S. EPA, WaterSense).
- EPA's toilet dye test takes 10 minutes: add a few drops of food coloring to the tank and wait. Color in the bowl points to a leaking flapper (U.S. EPA, WaterSense).
- Fix plumbing leaks as soon as possible, since wet materials can grow mold and a steady leak adds to your water bill (U.S. EPA).
On this page
- Is a Leak in Your House an Emergency Right Now?
- How Do You Stay Safe If Water Is Near Electrics?
- How Do You Shut Off the Water Fast?
- Where Is the Main Water Shutoff, and What If It Will Not Turn?
- Where Is the Leak in Your House Coming From?
- How Can You Tell If the Leak Is Inside the House or in the Supply Line?
- Is a Slow Drip or Small Leak Worth Worrying About?
- Should You Fix the Leak Yourself or Call a Plumber?
- Will Homeowners Insurance Cover a Leak, and What Should You Document?
- How Fast Do You Need to Dry a Leak to Prevent Mold?
- What If the Leak Is in a Rental, a Condo, or From the Unit Above?
- When to call a professional
- Frequently asked questions
Is a Leak in Your House an Emergency Right Now?
Treat it as an emergency if water is flowing fast or spreading, reaching outlets, switches or appliances, or if a ceiling is bulging. A slow leak still needs a prompt repair, but you usually have time to shut it off, catch the water, and call a plumber.
If a pipe has suddenly burst and water is coming out fast, follow the first-hour steps in our guide on what to do when a pipe bursts. If the water is coming through a ceiling instead, see what to do when water drips through a ceiling.
| What you see | Level | What to do now |
|---|---|---|
| Water flowing fast or spreading across the floor | Emergency | Shut off the water, stay out of standing water, and call a plumber now |
| Water reaching outlets, switches or appliances | Emergency | Do not touch wet electrics. Follow the electrical rule in the next section |
| Ceiling bulging, sagging or dripping heavily | Emergency | Move people out from under it and see our ceiling-leak guide |
| Steady drip or seep in one spot | Urgent, not an emergency | Shut off the source if you can, catch the water, and schedule a repair soon |
| Damp spot or stain, nothing wet right now | Urgent | Find the source and dry the area before it spreads |
The U.S. EPA recommends fixing plumbing leaks and other water problems as soon as possible, so do not leave even a small, steady drip for later.
How Do You Stay Safe If Water Is Near Electrics?
Do not touch any electrical equipment that is wet, and do not stand in water to reach it. Turn off the electricity only if you can do it safely. If you cannot, call the utility or an electrician and stay out of the water.
Ready.gov warns that underground or downed power lines can electrically charge standing water outdoors, and that you should turn off electricity only when it is safe to do so.
- Stay on a dry floor, away from the water.
- Do not touch plugs, cords, switches or appliances that are wet.
- Do not walk into standing water to reach a breaker or fuse box.
- If you can reach the power off safely, turn it off.
- If you cannot reach it safely, call the utility or an electrician and stay out of the water.
If you smell gas at any point, leave the house and call the gas company from outside before doing anything else.
How Do You Shut Off the Water Fast?
Close the valve closest to the leak first: a fixture shutoff under a sink or behind a toilet, or the valve on an appliance supply line. If you cannot find or close it, shut off the main valve for the whole house.
- Shut the fixture valve closest to the leak, if there is one.
- Shut the appliance supply valve for a washer, dishwasher or refrigerator leak.
- If you cannot find or close those, shut the main valve for the house.
Where Is the Main Water Shutoff, and What If It Will Not Turn?
The main valve is on the line where water enters the house, often near the water meter. If it will not turn, do not force it. Call your water utility or a plumber.
- Look where the main water line enters the house, often near the water meter.
- Check your water utility's website for the exact location in your area.
- If the valve will not turn, do not force it. Call the utility or a plumber.
For step-by-step help finding yours, see our guide on how to find your main water shutoff valve.
Where Is the Leak in Your House Coming From?
Check the common sources first: under sinks, toilet bases and tanks, appliance hoses, the water heater, and the ceiling or wall above or beside the water. If none of these show a drip, the leak is probably hidden.
| Likely source | Clue | Next step |
|---|---|---|
| Under a sink or behind a toilet | Drip at a joint, supply line or valve; water pooling at the base | Shut the fixture valve, dry the floor, then tighten or replace the part |
| Water heater or an appliance hose | Water pooling at the tank base or behind a machine | Shut the appliance supply valve. For a water heater, see our guide on a water heater leaking from the bottom |
| Ceiling | Stain, drip or bulge below a bathroom or an upstairs floor | Go back to the emergency check above, or see our ceiling-leak guide |
| Wall | Damp paint, bubbling, or a musty smell with no visible drip | See our guide on water that is inside a wall |
| Unknown or hidden | High water bill or a damp floor with no visible drip | Use the water meter test in the next section to narrow it down |
Visible sources (fixtures and appliances)
Most leaks start at a fixture or appliance: a worn washer, a loose supply line, or a cracked hose. These are usually the easiest to find and the cheapest to fix once the water is off.
Leaks you cannot see
A leak inside a wall, under a slab, or in the line between the meter and the house will not show a visible drip. A high water bill or a damp area with no clear source is a sign of a hidden leak. The meter test below can confirm whether one exists.
How Can You Tell If the Leak Is Inside the House or in the Supply Line?
Turn off all water use, read your water meter, wait two hours with no water used, and read it again. The EPA's WaterSense program says that if the reading is not the same after two hours, you could have a leaky bathroom fixture or hose.
- Turn off every tap, appliance and toilet use. Do not flush.
- Read the water meter and write the number down.
- Wait two hours with no water used.
- Read the meter again. If the number changed, you may have a leak.
Two-hour meter check
This test catches leaks you cannot see, including a running toilet or a slow fixture leak. Two hours is the EPA's recommended wait, not one hour, since a shorter wait can miss a small leak. For the full version with more steps, see our guide on the full water meter leak test.
Ten-minute toilet dye test
Add a few drops of food coloring to the tank at the back of the toilet and wait 10 minutes without flushing. The EPA says that if color shows up in the bowl, you have a leak and should consider replacing the flapper.
If the meter still moves with the main valve shut off, the leak is likely between the meter and the house, or outside. Call the water utility or a plumber.
Is a Slow Drip or Small Leak Worth Worrying About?
Yes. The EPA advises fixing plumbing leaks and other water problems as soon as possible, since wet materials can grow mold and a steady leak adds to your water bill.
- A stain that grows or changes shape.
- A damp floor, cabinet base or baseboard.
- A musty smell with no visible source.
- A water bill that rises with no change in how you use water.
- A meter that moves during the two-hour test above.
Should You Fix the Leak Yourself or Call a Plumber?
Call a plumber when the source is unclear, the leak is inside a wall or ceiling, water keeps coming after the valves are closed, or the repair means cutting or joining pipe. A loose fitting or a worn toilet flapper can often be a simple fix once the water is off.
| Task | Can a homeowner try it? | Call a pro if |
|---|---|---|
| Tighten a loose fitting under a sink | Often yes, once the valve is shut | The fitting is corroded or the joint keeps leaking |
| Replace a worn toilet flapper | Often yes; the dye test above points to the flapper | The tank or bowl is cracked, or the leak continues |
| Find a leak inside a wall or ceiling | No, not safely | Always |
| Cut, solder or join pipe | Only with real plumbing experience | Otherwise |
| Water keeps coming after the valves are closed | No | Right away |
If the leak turns out to be a sudden burst pipe rather than a slow one, our guide on how to fix a burst pipe covers the repair steps. Ask any plumber for a written estimate before work starts.
Will Homeowners Insurance Cover a Leak, and What Should You Document?
Policies usually cover sudden, accidental water damage and often exclude slow, repeated leaks, so read your own policy and report the damage promptly. Before cleanup, photograph the source, the damage and the meter reading, and keep your receipts. This is general information, not advice about your specific policy.
- Photos and video of the source, the damage and the wet area, with the date.
- The meter reading from the test above, if you took one.
- Receipts for emergency repairs and drying.
- A written list of damaged items.
For how coverage usually works for this kind of damage, see our guide on whether homeowners insurance covers a burst pipe.
How Fast Do You Need to Dry a Leak to Prevent Mold?
Dry water-damaged areas and items within 24 to 48 hours to prevent mold growth, according to the EPA. Anything still wet after that needs help from a drying professional.
| Item or area | What to do | Source |
|---|---|---|
| Carpet, ceiling tiles and other porous items | Dry them fully. They may have to be thrown away if they become moldy | EPA, Mold Cleanup in Your Home |
| Any area still wet after 24 to 48 hours | Call for drying help | EPA, A Brief Guide to Mold, Moisture and Your Home |
| A moldy patch under about 10 square feet | A homeowner can often clean it using EPA guidelines | EPA, A Brief Guide to Mold, Moisture and Your Home |
| Anyone with asthma, lung conditions or a weak immune system | Keep them out of buildings with indoor leaks or visible or smelly mold | Ready.gov, Floods |
If the water came from sewage or another contaminated source, the EPA advises calling a professional who has experience cleaning buildings damaged by contaminated water.
What If the Leak Is in a Rental, a Condo, or From the Unit Above?
Tell the landlord, property manager, HOA or upstairs owner right away, in writing, with the date and the location of the water. Who to call first depends on where the leak starts.
- Leak inside your rental unit: contact the landlord or property manager.
- Leak from the unit above: contact the upstairs owner or tenant, and the building manager or HOA.
- Leak in a shared pipe or wall in the building: contact the building manager or HOA.
- Leak at or before the water meter: contact the water utility.
- Leak inside your own condo unit: check the HOA rules, which set what is shared.
When to call a professional
Call for help now if any of these are true:
- Water is flowing fast or spreading across the floor.
- Water is at outlets, switches or appliances and you cannot safely keep away from it.
- A ceiling is bulging, sagging or dripping heavily.
- You cannot find or close any valve, or the valve will not turn.
- The water keeps coming after the valves are closed.
- The water is sewage or otherwise contaminated. The EPA advises calling a professional experienced in cleaning buildings damaged by contaminated water.
Call soon, even if it is not an emergency, if:
- The meter still moves with every fixture and the main valve shut off. Call the water utility or a plumber.
- You cannot find the source after checking the common spots above.
- An area is still wet 24 to 48 hours after you found the leak, the EPA's target for preventing mold.
- A moldy patch is larger than about 10 square feet.
- The leak comes back after a repair.
Electrics and water: do not touch electrical equipment that is wet, or stand in water to reach it. Turn off the electricity only if it is safe to do so, per Ready.gov. If you cannot reach it safely, call the utility or an electrician and stay out of the water.
Health: Ready.gov says people with asthma, other lung conditions or a weak immune system should not enter buildings with indoor water leaks or mold growth that can be seen or smelled.
Gas: if you smell gas at any point, leave the house and call the gas company from outside.
Frequently asked questions
How do I know if the water is sewage?
Sewage usually comes from a toilet, drain or sewer backup, and it may look gray or black or smell foul. The EPA says that if water damage was caused by sewage or other contaminated water, you should call a professional who has experience cleaning and fixing buildings damaged by contaminated water. Keep people and pets out of the area until then.
Can I stay in the house while a leak is being fixed?
It depends on the water, the electrics and any mold. Ready.gov says people with asthma, other lung conditions or weak immune systems should not enter buildings with indoor water leaks or visible or smelly mold. If anyone in your home has these conditions, keep them out of the affected area and plan a place to stay until it is dry and repaired.
Do I need to turn off the power to the whole house?
Only if it is safe and you cannot keep away from wet electrical equipment. Ready.gov says do not touch electrical equipment that is wet or stand in water, and turn off the electricity only if it is safe to do so. If you cannot reach a switch safely, stay out of the water, call the utility or an electrician, and wait for them to arrive.
How can I tell if a leak is getting worse?
Mark the edge of a stain or wet spot with a pencil and write the date and time next to it. Check it again later that day and the next day, and take a photo at each check. If the stain has grown past the pencil line, the leak is spreading and needs a faster response.
Should I call the water utility or a plumber first?
Call the water utility if the leak is at or before the water meter, or if the meter still moves with all water off and you cannot find the source inside. For leaks at fixtures, pipes or appliances inside the house, call a plumber. If you are not sure, call a plumber first, since a plumber can help find the source and tell you when the utility is needed.
How much does it cost to fix a water leak?
The price depends on where the leak is, how hard it is to reach, and the parts needed. A plumber charges a service fee plus parts. Ask for a written estimate before work starts, and compare two quotes if the job looks large.