What Will Your Water Bill Actually Cost?
Select your state for a live water + sewer rate, set your household size and usage habits, and see your real annual and monthly bill — plus how much leaks and outdoor watering add.
The average US household uses ~82 gallons per person per day — but outdoor watering and hidden leaks can push your bill 50%+ above that baseline.
82 gal
EPA WaterSense average per person per day — the baseline for indoor residential use
2.7×
Rate spread: Hawaii ($14.50/1k gal) vs West Virginia ($5.40/1k gal) — same usage, vastly different bills
50 states
Live state water + sewer rates — refreshed regularly via Apify so you get a real local number
What actually drives your water bill
Your state rate is the biggest variable
Combined water + sewer rates range from ~$5.40/1,000 gal in West Virginia to ~$14.50 in Hawaii. A 3-person household on average use (~89,790 gal/year) pays $485 in WV and $1,302 in Hawaii — a $817/year gap for identical usage. That's why we load your state's live rate instead of a generic national guess.
Outdoor watering is the silent bill-killer
Indoor use is relatively predictable at ~82 gallons per person per day. Outdoor irrigation — lawns, pools, garden hoses — can add 20–45% to total use in dry climates. In Arizona and Nevada, where rates already run $10–11/1,000 gal, a heavy-watering household can easily exceed $1,500/year.
Leaks waste more than you'd think
A running toilet can waste 200 gallons/day; a dripping faucet adds 3,000 gallons/year. EPA WaterSense estimates the average home with a leak wastes ~10,000 gallons annually — about 10% of the bill. Fixing a $15 flapper often pays for itself in the first month.
How the Water Bill Calculator Works
Formula
Daily Gallons = People × 82 GPCD × Usage Level × Outdoor Factor
Annual Gallons = Daily Gallons × 365
Effective Rate = State Rate × (Water-only ? 0.52 : 1.0)
Annual Cost = (Annual Gallons ÷ 1,000) × Effective Rate
Monthly Cost = Annual Cost ÷ 12Select your state
Loads your state's live combined water + sewer rate ($/1,000 gallons). Rates range from ~$5.40/1k gal (West Virginia) to ~$14.50/1k gal (Hawaii) — roughly 2.7× spread for the same household.
Set household size
Number of people in your home. Water use scales linearly — EPA baseline is 82 gallons per person per day. US average household is 2.5–3 people (~205–246 gal/day).
Choose indoor usage level
Low = WaterSense fixtures and shorter showers (75% of EPA avg). Average = typical US household (100%). High = long showers and frequent laundry (135%).
Select outdoor watering
None = no lawn/garden irrigation. Seasonal adds 20% to daily gallons (spring/summer lawn). Heavy adds 45% — large yards in dry climates like Arizona or Texas.
Bill includes sewer?
Combined (default) uses the full water + sewer rate. Water-only applies a 52% fraction for septic systems or when sewer is billed separately — per AWWA typical rate structure.
At default settings — 3 people, average indoor use, no outdoor watering, combined billing — the national rate of $8.00/1,000 gal produces ~246 gallons/day and an annual bill of about $718 ($60/month). Every example on this page is recomputed from the same formula the calculator uses.
State rates are refreshed regularly via Apify from published average monthly bill data, converted to $/1,000 gallons using the EPA reference household. If a refresh fails, safe static fallbacks keep the app running — the last good numbers stay in place until the next successful run.
Frequently Asked Questions
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