Water Usage Cost Calculator
Estimate household water use and utility cost from occupants, daily indoor use, outdoor use, billing days, variable rates, sewer percentage and fixed charges.
Default project preview
$199.96
Daily water use
270 gal
Billing-period volume
8,100 gal
Water charge
$97.20
Sewer charge
$77.76
Calculator
Build the material order
Your order will appear here
Enter the project details and calculate a rounded material estimate.
Input and output guide
What each value means
The labels and units below are part of this calculator’s visible methodology. Replace every default with measurements or product data from the actual project.
Household occupants
Enter this project assumption in a unitless value. The current imperial default is 4. Minimum: 1.
Indoor use per person
Enter this project assumption in gal/day. The current imperial default is 60 gal/day.
Average outdoor use
Enter this project assumption in gal/day. The current imperial default is 30 gal/day. Minimum: 0.
Billing-period days
Enter this project assumption in days. The current imperial default is 30 days. Minimum: 1.
Water rate
Enter this project assumption in per 1,000 gal. The current imperial default is 12 per 1,000 gal. Minimum: 0.
Sewer charge
Enter this project assumption in % of water charge. The current imperial default is 80 % of water charge. Minimum: 0. Maximum: 300.
Fixed billing charge
Enter this project assumption in a unitless value. The current imperial default is 25. Minimum: 0.
How to read the outputs
Daily water use
indoor plus outdoor. Default preview: 270 gal.
Billing-period volume
entered schedule. Default preview: 8,100 gal.
Water charge
variable water rate. Default preview: $97.20.
Sewer charge
80% of water charge. Default preview: $77.76.
Fixed charge
entered billing fee. Default preview: $25.00.
Annualized cost
same usage pattern. Default preview: $2,432.85.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Daily use = occupants × indoor use per person + outdoor use. Billing volume multiplies by days. Variable water charge uses thousands of gallons or cubic metres, then sewer and fixed charges are added.
Related tools
Continue planning the project
BuildMeter Guides
Understand the measurements and assumptions
Use these visible reference guides before changing project inputs or planning allowances.
FAQ
Water Usage Cost Calculator questions
Why might my bill be higher than this estimate?+
Tiered rates, taxes, fixed fees, leaks and seasonal outdoor use can increase actual bills.
Is sewer always based on total water use?+
No. Some utilities exclude irrigation or use separate winter averages and billing rules.
Can this help compare conservation measures?+
Yes. Reduce daily-use inputs to compare approximate volume and cost changes.