How do I figure out why my water bill spiked?
Compare the high bill with an earlier bill using gallons, total dollars, fixed fees, sewer charges, and the all-in cost per 1,000 gallons.
Water bill spike calculator
Compare two water bills and find the likely spike driver.
Enter the earlier bill and the high-bill month to compare gallons, total dollars, fixed fees, sewer charges, and all-in cost per 1,000 gallons.
Water bill
$114
Water use$46.00
Sewer$41.00
Service$27.00
All-in rate
$15.83 per 1k gal
Best next check
Leak and irrigation
Compare two water bills
Use gallons and non-usage fees to separate leaks from sewer, base, and stormwater pressure.
Bill change
$68.00
79% compared with the earlier bill.
Usage change
2,600 gal
50% compared with the earlier month.
Fee change
$17.00
Current fixed and sewer fees are entered as $62.00.
First diagnosis
Usage up
Usage appears to be the main driver. Check toilets, irrigation, outdoor watering, guests, softener cycles, and hidden leaks first.
All-in water cost
Previous bill: $16.54 per 1,000 gallons. Current bill: $19.74 per 1,000 gallons. Usage-only rate moved from $7.88 to $11.79 per 1,000 gallons after the fixed/sewer fees you entered.
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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Check the spike from another angle
Water meter reading calculator
Check whether the previous and current meter reads explain the gallon change.
Open pageHigh water bill diagnosis
Review gallons, sewer charges, fixed fees, irrigation, leaks, and meter reads.
Open pageWater bill audit checklist
Use a step-by-step checklist to compare usage, fees, and meter details.
Open pageFAQ
Short answers for search visitors and bill-checking moments.
What if gallons increased more than the bill?
Usage is probably the first place to investigate. Check toilet flappers, irrigation schedules, outdoor watering, guests, water softeners, and hidden leaks.
What if gallons stayed flat but the water bill increased?
Review non-usage line items such as sewer, stormwater, base charges, minimum bills, taxes, meter estimates, and local rate changes.