Leaky Faucet and Running Toilet: Gallons Wasted per Year and What It Costs
October 29, 2026
Small leaks add up because they run 24 hours a day. The US EPA's WaterSense program estimates that a faucet dripping at one drip per second wastes more than 3,000 gallons per year, and that a leaking toilet can waste about 200 gallons per day. Families lose water without noticing, as toilet leaks are often silent.
Convert to cost using your water and sewer rate. If the combined rate is $10 per 1,000 gallons, 3,000 gallons cost $30 a year, and 200 gallons a day (73,000 gallons a year) costs $730.
Skip the math and get your answer instantly:
Open the Volume Calculator →Cost Table
The table shows annual waste for different leaks. A slow toilet leak of 30 gallons a day is 10,950 gallons a year ($110). A steady fine stream from a leaking toilet flapper might waste 6 gallons per hour, or 144 gallons a day (52,560 gallons, $526). If your rates are higher ($15 to $20 per 1,000 gallons in some areas, including sewer charges), the cost grows proportionally. Hot water leaks also waste energy: 3,000 gallons of water heated by 70°F with an electric water heater costs about 3,000 × 8.34 × 70 ÷ 3,412 = 513 kWh, or $82 at $0.16 per kWh.
| Leak | Gallons per day | Gallons per year | Cost at $10 per 1,000 gal |
|---|---|---|---|
| Faucet, 1 drip/sec | 8.2 | 3,000 | $30 |
| Slow toilet leak | 30 | 10,950 | $110 |
| Running toilet, small | 144 | 52,560 | $526 |
| Running toilet, EPA estimate | 200 | 73,000 | $730 |
The Dye Test
Put 10 to 15 drops of food coloring into the toilet tank (not the bowl). Don't flush for 15 minutes. If color appears in the bowl, the flapper or fill valve is leaking. Replacement parts cost $5 to $25 and take 10 to 20 minutes to install. Also check the water meter: turn off all water, note the reading, wait 30 minutes to a couple of hours, and check again; any movement indicates a leak somewhere. Many meters have a small leak indicator dial.
Fixing the Most Common Leaks
Dripping faucets are usually worn washers, O-rings, or cartridges ($3 to $20 in parts). A running toilet often needs a new flapper or fill valve. Leaking showerheads and hose bibs also add up. Compare the repair cost with the annual savings: a $10 flapper that stops a 144-gallon-a-day leak pays for itself in about a week. Older toilets (pre-1994) use 3.5 to 7 gallons per flush, so replacing them with a 1.28-gallon model saves a lot; see WaterSense-labeled products.
Bill Spikes
If your water bill jumps, a leak is a possible cause. Many utilities offer leak adjustments on sewer charges for some qualified leaks, and some provide alerts for continuous use. Check irrigation systems for leaks as well, as they can be hard to notice outdoors.
Frequently Asked Questions
How much does a dripping faucet waste?
More than 3,000 gallons a year at one drip per second.
How much can a leaking toilet waste?
About 200 gallons per day, according to EPA estimates.
How does the dye test work?
Food coloring in the tank shows up in the bowl if the flapper leaks.
Is it worth fixing a small leak?
Yes, parts are cheap and savings add up.
How can I use the meter to find leaks?
Turn off all water use and see whether the meter still moves.