Step 1
Confirm the billing period
A longer cycle can make the bill look high. Compare gallons per day or CCF per day before comparing totals.
Water bill audit
Audit a high water bill before replacing fixtures.
Work through the bill in order: billing days, usage units, sewer charges, leaks, outdoor use, fixed fees, and meter reads. The goal is to find the cause before guessing at the fix.
Quick worksheet
Billing days
Was this bill longer than the last water bill?
Usage per day
Did daily gallons or daily CCF increase?
Sewer line
Is sewer fixed, usage-based, capped, or estimated?
Leak check
Does the meter move when all fixtures are off?
Outdoor use
Did irrigation, pool fill, or hose use change?
Meter read
Was the reading actual, estimated, corrected, or adjusted?
Step 2
Convert the usage unit
Water bills may use gallons, thousand gallons, CCF, or cubic feet. Convert the unit so the usage trend is clear.
Step 3
Separate water and sewer
Sewer can be usage-based, fixed, capped, or seasonal. A water savings estimate is incomplete until sewer is separated.
Step 4
Check continuous leaks
Toilet flappers, irrigation lines, service-line leaks, and softener cycles can add water every hour of the month.
Step 5
Review fixed charges
Base charges, meter fees, stormwater charges, and minimum bills may not change even if household usage falls.
Step 6
Flag meter or estimate issues
Estimated reads, catch-up reads, meter replacements, and tier resets can create a sudden bill change.
Audit rule
Do not estimate savings until water, sewer, and fixed fees are separate.
A useful audit compares daily gallons first, then the sewer calculation, then fixed lines. This prevents the common mistake of expecting every saved gallon to reduce every bill line.
After you isolate the cause, use the savings calculator to estimate the value of a leak fix, irrigation change, or fixture upgrade.
Useful checks
Tools that can make the estimate more accurate
Water leak detector
Helps catch hidden leaks under sinks, near water heaters, or around laundry areas.
Toilet leak detection tablets
A low-cost way to check whether a toilet flapper is wasting water.
Low-flow shower head
Can reduce water use for households where showers drive the monthly bill.
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Water bill audit tools
Water bill explainer
Understand usage, sewer, stormwater, meter, base, and tax lines.
Open pageAverage water bill
Compare monthly cost and gallons against normal household ranges.
Open pageWater bill calculator
Rebuild the bill from usage, base fees, sewer, stormwater, and taxes.
Open pageSewer bill calculator
Separate sewer usage, fixed sewer fees, caps, and wastewater rules from water usage.
Open pageTiered water bill calculator
Check whether high-use tiers made the marginal gallons more expensive.
Open pageHigh water bill diagnosis
Use a broader troubleshooting path for sudden water bill increases.
Open pageWater leak calculators
Estimate the cost of toilet, faucet, shower, irrigation, and pipe leaks.
Open pageWater savings calculator
Estimate the value of reducing monthly gallons after the audit.
Open pageHow to lower your water bill
Move from audit findings to practical leak, irrigation, and sewer checks.
Open pageToilet leak water cost
Estimate a silent running toilet if usage rose every day of the billing period.
Open pageShower water cost
Compare shower flow rate and minutes when indoor usage looks high.
Open pageSummer utility bill calculator
Audit a warm-weather bill that mixes outdoor water with higher electric use.
Open pageFAQ
Short answers for search visitors and bill-checking moments.
What is the first thing to check on a high water bill?
Check billing days and usage per day first. Then confirm whether the increase is water usage, sewer, fixed fees, or an estimated meter adjustment.
How do I know if a leak caused the high water bill?
Turn off fixtures and watch the meter. If the meter still moves, or if usage is high every day, check toilets, irrigation, service lines, and outdoor spigots.
Can sewer charges make water savings look smaller?
Yes. Sewer may be fixed, capped, billed from winter averages, or calculated separately. Separate sewer before estimating savings from lower gallons.