How to read your water meter and check for leaks

Your meter can help explain a high bill before the next one arrives.

The answer in 2 lines. Start by identifying the unit printed on your meter: US meters may measure gallons or cubic feet, and the billing unit may represent a larger quantity. Photograph the entire display, record the date and compare readings in the same units. Do not assume red digits mean liters. To check for a leak, stop all indoor and outdoor water use and compare readings before and after a two-hour period. If the reading changes, investigate water-using equipment and possible leaks.

The first 3 steps

Locate the correct meter. Look for an accessible indoor meter or an outdoor meter box near the street. In a building with shared equipment, ask management which meter serves your unit.
Photograph the full display. Include the unit markings, decimal point and any fixed zeros. Record the date so you can compare it with another reading.
Check the identification. Compare the meter identifier with your bill where available. Ask for clarification before interpreting an unfamiliar shared or replacement meter.

Stop: danger

Unsafe access: leave a locked, damaged, flooded or unusually heavy meter cover alone. Request help through the contact information printed on your water bill.
Meter equipment: do not disturb seals, disconnect wires or attempt to operate unfamiliar street-side valves. Replace an accessible cover securely after reading.

Understand the display before doing the math

The register is a running total, much like an odometer. Read it from left to right, but check your local instructions for decimals, fixed zeros and the digits used for billing. A separate flow-rate screen shows current use rather than the accumulated total.

For a visual example, open New York City's meter-reading instructions and compare the display illustrations with your meter. These instructions apply to local equipment; they are not a nationwide digit rule.

Units also differ. Napa's meter-reading page illustrates a gallons register and explains its billing units. Use it to understand why the number on a bill may omit smaller quantities shown on the meter.

What not to do

Treating digit colors as a universal code: the layout depends on the meter.
Comparing gallons on the meter directly with hundreds of cubic feet on a bill.
Comparing different time periods without checking the reading dates.
Assuming movement proves a broken pipe: irrigation, toilets and automatic equipment may still be using water.

Track consumption and investigate movement

Subtract the earlier reading from the later reading, keeping the same units and decimal positions. Keep dated photographs in a simple log. Compare similar periods and note changes such as visitors, irrigation or an absence.

For a cubic-foot example, use San José's reading guide: it explains that HCF and CCF mean hundred cubic feet, equivalent to 748 gallons. This is a unit conversion, not an annual consumption estimate.

For the leak test, follow EPA WaterSense's household leak guidance. Stop faucets, flushing, laundry, dishwashing and outdoor watering. Account for automatic equipment, leave the water supply on, and compare readings before and after two hours. A change suggests a leak or an overlooked water use. Check toilets and visible connections, then seek a licensed plumber if the source remains unclear.

When the bill does not match

Check whether the bill uses an actual or estimated reading, its reading date and its unit multiplier. A current reading naturally includes water used since the billing date. A lower current reading needs explanation, particularly if the meter was recently replaced.

In Miami-Dade, follow the official meter comparison instructions: compare the register with the bill's Current Reading, then use the customer-service contact on that page to request a review if appropriate. Elsewhere, send your dated photograph using the contact on your own bill. Ask whether a leak adjustment exists and what evidence it requires; eligibility is local.

Good to know

A building's master meter measures the building's use. It cannot isolate your apartment's consumption without separate metering.
Record readings when moving in or out and before an extended absence, where you have safe access.
An unchanged reading during a short test does not rule out an intermittent leak.

Illustrative example: a homeowner in Napa notices a higher bill. She photographs the gallons register, checks the billing dates and repeats a reading without using water. The total rises. She finds a toilet refilling by itself and arranges a repair, then repeats the test.

A made-up story, for illustration.

Bobby

Sources, verification, confidence

Verified on November 4, 2026, for the United States. Confidence: high for reading principles and the EPA leak test; medium for application to an individual meter. Display layouts, billing units and adjustment policies vary locally.