How Much Does Water Cost per Gallon?

Tap water in the United States costs roughly 1 to 2 cents per gallon. EPA WaterSense puts the 2024 national average residential rate at $7.74 per 1,000 gallons for water and $9.09 per 1,000 gallons for wastewater — about 0.8 cents and 0.9 cents per gallon — or $16.83 per 1,000 gallons (about 1.7 cents per gallon) combined. Your own rate could sit well above or below that, because every utility sets its own prices. Here's how the numbers break down, why they vary, and how to find your exact cost per gallon.

Skip the math Water Cost per Gallon Calculator Open →

Water cost per gallon at a glance

Utilities rarely quote a price per gallon. They bill per 1,000 gallons or per CCF, so it helps to see the same national average expressed in each unit:

Two things stand out. First, water is cheap per gallon: you could use 100 gallons for under a dollar in water charges. Second, the sewer side of the bill is larger than the supply side. At national average rates, wastewater costs more per gallon than the water itself, so the sewer line deserves as much attention as the water line.

These are national averages that EPA WaterSense estimates from American Water Works Association rate surveys. They describe a typical rate, not the rate you pay. Actual bills also include fixed service charges and sometimes stormwater fees.

Cost by volume, quick reference

Most real questions aren't about a single gallon. They're about a bucket, a bath, a month of use or a pool fill. Here's what common volumes cost at the national average rates above:

The cost scales in a straight line, so you can work out any other volume yourself: multiply gallons by 0.00774 for water only, or by 0.01683 for water plus sewer.

EPA says the average American family uses more than 300 gallons of water per day at home. At combined national average rates, 300 gallons is roughly $5.05 a day. That is an upper-end picture: 300 gallons a day, all billed at both rates, comes to about $150 a month. Real bills often run lower, because EPA's figure is an average and utilities that base sewer charges on indoor use don't bill sewer on irrigation.

Why the price per gallon varies so much

There's no single national price, because water is a local utility service. Each system sets rates to cover its own costs, and those costs differ more than most people expect. The main drivers are:

• Source and treatment. A utility pumping clean groundwater has lower treatment costs than one drawing from a river or reservoir, and a system that buys water from a regional supplier passes that wholesale cost on.
• Aging infrastructure. Pipes, pumps and treatment plants are expensive to replace, and much of that cost is fixed. EPA lists higher water prices among the consequences of strained supplies and aging delivery systems.
• Scarcity and climate. Dry regions pay to secure and move limited supply, and heavy summer irrigation forces utilities to build for peak demand.
• Sewer and stormwater costs. Wastewater treatment is often the larger half of the bill, and it varies just as much by city.
• Rate design. Fixed fees, flat rates and tiered rates all change what a gallon effectively costs you.

To see how far a real utility can sit from the average, take Boston Water and Sewer Commission's 2026 residential schedule. It lists $9.384 per 1,000 gallons for water and $8.914 per 1,000 gallons for sewer in its lowest-use tier, and the water rate climbs to $12.764 per 1,000 gallons in its highest tier. Adding the two lowest-tier figures gives roughly $18.30 per 1,000 gallons, a little above the national combined average.

How utilities build your bill

A typical residential bill has up to four parts:

• A fixed service charge, which you pay however much water you use. Some utilities set it by meter size.
• A water volume charge, billed per 1,000 gallons or per CCF.
• A sewer or wastewater charge, usually calculated from your metered water use.
• Other fees, such as stormwater, that may be flat or based on property size.

Meters usually read in cubic feet, so many bills use CCF, meaning hundred cubic feet. According to the City of Portland's bill guide, one CCF equals 748 gallons. A rate of $5 per CCF is therefore not $5 per gallon but about 0.67 cents per gallon. Mixing up the units is the most common reason people misread their water price.

Rate structure matters too. A uniform rate charges the same price for every gallon. A tiered (increasing-block) rate charges more per gallon as your use climbs through each band, which is how Boston's schedule works across its six tiers. Tiers reward low use and make heavy irrigation or leaks disproportionately expensive. Many utilities also base the sewer charge on water use, and some use a winter average so summer watering isn't charged for sewer.

Calculate your own cost per gallon

Your bill has everything you need. For the real average price you pay, divide the total charges by the gallons you used:

If your utility prints a rate per CCF and you want it per gallon, divide by 748:

The two numbers answer different questions. The all-in figure includes fixed fees, so it reflects what you actually pay on average. The volume rate alone is the price of your next gallon, and that's the one that matters when you're deciding whether a leak repair or low-flow fixture will pay off. The water cost per gallon calculator does this arithmetic from the numbers on your bill.

Hot water costs more than the water itself

The utility charge is only part of what a gallon costs at the tap. Heating adds an energy cost, and for hot water that usually outweighs the water and sewer charges. EPA WaterSense's residential working figure for electric water heating is about 0.16 kWh per gallon heated.

At an illustrative electricity price of 15 cents per kWh, that is roughly 2.5 cents per gallon, more than the roughly 1.7 cents for water and sewer combined. Gas heating changes the arithmetic, but the principle holds: a hot gallon costs noticeably more than a cold one. That's why a shorter hot shower saves on both the water bill and the energy bill.

Tap water vs bottled water

Seen in cost per gallon, the gap between tap and bottled water is enormous. Bottled prices vary by brand and store, so treat these as rough estimates:

A single half-liter bottle at $1 to $2 works out to roughly $7 to $15 per gallon, hundreds of times the cost of tap water. Even a cheap multipack runs dozens of times higher. Whether that's worth it is a question of taste, convenience or confidence in your local supply, not of cost. If taste is the issue, a filter adds the price of replacement cartridges, which still leaves the water far cheaper than bottled.

Real-world examples

Some numbers are easier to trust when attached to something you can picture. All figures are estimates at 2024 national average rates:

The bottom line

At the 2024 national average, tap water costs about 0.8 cents per gallon for the water itself and about 1.7 cents per gallon once sewer is included, or $16.83 per 1,000 gallons. Your price will differ with your utility, your rate tier and the fixed fees on your bill. To find your own number, convert your usage to gallons (1 CCF is 748), divide your charges by that figure, and remember that heating water costs more than the water itself.