Water Bill Calculator
Estimate your water bill from metered use in gallons, CCF or m³, or from a household usage estimate, with flat or tiered rates, fixed service charges, sewer charges, other fees and taxes. Shows monthly and yearly totals, a tier breakdown and the bill at other usage levels.
How it works
usage charge = Σ over tiers (water in tier ÷ 1,000 gal × tier rate) · sewer = sewer volume × sewer rate, or usage charge × sewer % · bill = usage + fixed charge + sewer + other fees, plus tax · yearly = bill × bills per year · 1 CCF = 748 gal · 1 m³ = 264.2 gal
Water is metered by volume: gallons, thousands of gallons, CCF (hundred cubic feet, also called HCF or a “unit”, 748 gallons) or cubic meters. The usage is matched against your utility’s rate. With a flat rate every gallon costs the same. With tiered (inclining block) rates, the first block is billed at the tier 1 price, the next block at the tier 2 price, and so on, so only the water above each threshold pays the higher rate. Most bills add a fixed service or meter charge. Many also add sewer, either per volume (sometimes on 85–95% of the water, or capped at your winter average) or as a percentage of the water charge. Stormwater or trash fees and taxes come on top. No meter reading? Estimate mode builds the usage from people, showers, toilets, laundry, dishwasher, lawn watering and typical leaks.
Worked example
6,000 gallons at $5.00 per 1,000 gallons is $30.00 of usage. Add a $15.00 service charge and the bill is $45.00 a month, about $540 a year, or an all-in $7.50 per 1,000 gallons. With three tiers instead (5,000 gal at $3, then 5,000–15,000 at $5), the same 6,000 gallons cost $15 + $5 = $20 of usage. A sewer charge of $6 per 1,000 gallons plus $10 would add $46.
Sources: EPA WaterSense — how we use water · EPA WaterSense — statistics and facts (leaks 9,400 gal per home per year) · EPA WaterSense — residential toilets (1.6 and 1.28 gal per flush) · Denver Water — tiered residential rates per 1,000 gallons
Frequently asked questions
Where do I find my usage and rate?
Both are on your utility bill. Usage is the difference between two meter readings, listed in gallons, thousands of gallons, CCF/HCF (748 gallons) or m³. The bill or the utility’s rate sheet lists the rate per unit, any tier thresholds and the service charge. Pick the matching unit next to each field and the calculator converts.
How do tiered water rates work?
Each tier is a block of usage with its own price. With tier 1 up to 5,000 gallons at $3 and tier 2 at $5, using 6,000 gallons costs 5 × $3 + 1 × $5 = $20. Only the last 1,000 gallons pays the higher rate, not the whole bill. Many cities set tier 1 from your winter average use.
How is the sewer charge calculated?
Usually from your water use, since sewage is not metered. Some utilities charge a rate per 1,000 gallons or CCF, often on a set share of the water or capped at your winter average. Others charge a percentage of the water charge. Either way there is often a fixed sewer charge too. Sewer can cost as much as the water, or more.
How much water does a household use?
EPA says the average American family uses more than 300 gallons a day at home, about 9,000 a month, with roughly 30% going outdoors. Indoor use is about 50–80 gallons per person a day. Estimate mode breaks your use down by toilets, showers, laundry and leaks.
How can I lower my water bill?
Fix leaks first: a running toilet can waste 200 gallons a day. Then replace old toilets (3.5 gallons a flush down to 1.28) and showerheads, run full laundry and dishwasher loads, and water lawns early in the morning. Fixed charges stay the same, so the saving per gallon is the usage and sewer rate.
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This calculator is for educational purposes. Double-check important results before acting on them.