Utilities calculator

Water Bill Calculator

Estimate water cost from daily gallons, bill days, rate per thousand gallons, and fixed monthly fees.

Last reviewed: July 3, 2026 · Use case: planning estimate, comparison, and budgeting support.

When to use this calculator

Use this calculator for a quick water bill estimate when you know daily usage or want to compare conservation scenarios. It is useful for renters, homeowners, small apartments, gardens, and move-in budgets.

Water bills vary by city, provider, sewer fees, minimum charges, tiers, taxes, and fixed service fees. Treat the result as a planning number, not a utility statement.

Formula used

Water cost = gallons used ÷ 1,000 × rate per 1,000 gallons + fixed fees.

The formula is intentionally simple so it can be used for quick planning. Real bills, quotes, and installation costs can include fixed fees, taxes, tiers, labor, product limits, and site-specific conditions that a calculator cannot see.

Input guide

InputHow to use it
Gallons per dayEstimate household use, irrigation, laundry, showers, leaks, or appliance use.
Rate per 1,000 gallonsUse the rate from your provider or latest bill.
DaysUse the exact billing cycle when available.
Fixed feeAdd service charges, meter fees, or minimum monthly charges.

Examples

Basic household

150 gallons per day for 30 days equals 4,500 gallons before rates and fees.

Fixed-fee effect

A low-usage household can still have a noticeable bill because fixed service fees remain.

How to get a more accurate result

Common mistakes to avoid

Quick checklist before relying on the result

FAQ

Does this include sewer?

Only if you include sewer in the rate or fixed fee. Many providers bill sewer separately.

Why is my real bill higher?

Tiered pricing, taxes, sewer charges, minimum fees, and leaks can raise the actual bill.

Can this find a leak?

It cannot diagnose a leak, but comparing normal and current usage can show when something is unusual.

Related resources