Why Is My Water Bill So High? A Step-by-Step Diagnosis

Start with one question: more water, or a higher price?

A high bill has two possible sources. Either the meter recorded more water than usual, or the same amount of water cost more. Most bills show both the usage and the charges, so you can usually tell which one changed in a few minutes.

Put this bill next to the last one and, if you have it, the bill from the same month last year. Compare the usage number first, in the unit printed on the bill. If usage is about the same but the total jumped, skip to the section on prices and fees. If usage went up, keep going in order.

Step 1: Count the billing days

Billing periods are not always the same length. A 35-day bill will usually show more usage than a 28-day bill even if nothing changed in the house. Divide the usage by the number of days to get a daily figure, and compare that instead.

Here is an illustration with made-up numbers. Last bill: 4,200 gallons over 28 days, or 150 gallons a day. This bill: 5,600 gallons over 35 days, or 160 gallons a day. The total rose by a third, but daily use rose only about 7 percent. The site’s bill comparison calculator does this math for you and also works out cost per 1,000 gallons.

Step 2: Check whether the reading was actual or estimated

Look for a label such as “actual,” “estimated,” “E,” or “read type” next to the meter reading. If the last bill was estimated low, this bill may include water you actually used earlier. That is often called a catch-up bill. It looks like a spike, but it is really a correction.

Compare the current reading on the bill with the number on your meter today, if you can see the meter safely without opening a utility box. Your meter should read a little higher than the bill because time has passed. If it reads lower than the bill, the bill may be wrong, and you should ask the utility to check the reading.

Step 3: Run a two-hour quiet test

EPA’s WaterSense program suggests a simple test: note the meter reading, use no water for two hours, then read it again. If the meter moved at all, you probably have a leak. Do it when nobody is home or everyone is asleep, and turn off the ice maker, irrigation, and water softener first.

Some meters also have a small leak indicator that turns when any water flows. If it turns while everything is off, water is going somewhere. If your utility has a customer portal with hourly data, look for use between about 1 a.m. and 5 a.m. Steady overnight use is a strong clue.

• Write the reading down or take a photo with the time showing.
• Use no water at all for two hours.
• Read the meter again in the same unit.
• Any change means water moved. Repeat once to confirm.

Step 4: Check the toilets first

Toilets are one of the most common hidden leaks because they can run without making much noise. WSSC Water, which serves suburban Maryland, says a small toilet leak can waste about 200 gallons a day. It estimates that adds nearly $475 to a normal quarterly bill for its customers. Your local cost will differ, but the scale is the point.

To test a toilet, put a few drops of food coloring in the tank and wait 10 minutes without flushing. If color shows up in the bowl, the flapper or valve is leaking. Test every toilet in the house, including the one in the basement or guest room that nobody uses.

Step 5: Look for the other usual suspects

EPA says the average household’s leaks can waste more than 9,300 gallons a year. Nine percent of homes have leaks that waste 50 gallons or more a day. Besides toilets, the common sources are dripping faucets, irrigation systems, and outdoor hose bibs. A faucet dripping once per second can waste more than 3,000 gallons a year.

Also think about what changed in the household. Guests, a new baby, a teenager’s longer showers, filling a pool, or new landscaping can all raise use without any leak. EPA notes that outdoor use averages more than 30 percent of household water use and can be much higher in dry climates. Summer bills are often higher for that reason alone.

• Irrigation zones, drip lines, and timers that reset after a power outage
• Water softener stuck in a regeneration cycle
• Pool or fountain auto-fill valves
• Leaking water heater relief valve
• Outdoor spigots and hoses left connected in freezing weather
• Wet spots in the yard that never dry out

Step 6: Find out if the leak is inside or outside

If the quiet test shows water moving but you can’t find the source, Denver Water describes a next step. Close your home’s main shutoff valve and watch the meter. If the meter stops, the leak is inside the house. If it keeps moving, the leak may be in the underground service line between the meter and the house.

Only do this if you know where your main shutoff is and can operate it safely. Do not open the utility’s meter box or turn the utility’s valve. Who owns and repairs the service line depends on local rules, so ask the utility before hiring anyone to dig.

If usage didn’t change, look at prices and fees

If your daily use is steady but the bill is higher, check the rate lines. Utilities change rates from time to time, so check the effective date on the rate schedule. Tiered rates can also make a small increase in use cost a lot more, because the extra water is billed at a higher tier. Seasonal rates can make summer water cost more per gallon than winter water.

Then look at everything that isn’t water. Sewer is often billed from water use, and some cities base it on a winter average that lasts for months. Stormwater, trash, late fees, and an unpaid prior balance may also be on the same bill. A charge that didn’t exist last month is easy to spot once you list each line.

What to bring when you call the utility

A precise question gets a better answer than “my bill is too high.” Before you call, gather the bill, the prior bills you compared, your meter photos with times, and the result of your quiet test. Note any repair you already made and keep the receipt.

Ask the utility to confirm the reads used, whether any were estimated, and which rate schedule applied. If you found and fixed a leak, ask whether it offers a leak adjustment and what proof it needs. If the bill is due soon, ask what you need to pay to avoid late fees while it reviews the account. Get a case number.

When the bill is too high but correct

Sometimes the bill is right and you simply can’t pay it all at once. Ask about a payment plan before the due date, not after a shut-off notice. Many utilities also offer assistance or discount programs. Our guides on payment plans and on finding water bill assistance walk through both.