Operating cost
What a sump pump costs to run for a year
On the example inputs below, a year of running a sump pump costs $17.78 in electricity. People reasonably want that number — particularly when a contractor suggests a larger pump and it is not obvious whether that carries an ongoing cost — so the tool computes it from your own inputs rather than from horsepower.
Run hours are the part worth deriving. Nobody knows how many hours their pump ran last year, but everybody can estimate how many days it was wet and roughly how long the water kept arriving. Combine that with the pump's flow at your actual head and the run hours fall out: gallons that had to move, divided by gallons moved per hour.
Annual running cost from duty, not from horsepower
Illustrative assumption — not a market quote: every value filled in above is a worked-example starting point chosen by this site, not a measurement of your house. Replace each one with your own.
Electricity to run the pump for a year
$17.78
That is 96 kilowatt-hours across 129 hours of actual running.
Annual cost, low to high $10.67 to $32.01
Biggest swing factor How many hours a year water is actually arriving. Assumed, no direct source: the band shown is 0.6x to 1.8x the central figure, a width chosen by this site.
No flags from the numbers you entered.
Not included in this figure
- Motor starting surge on each start, which this tool does not model.
- Standby draw of a backup charger or controller, which runs every hour of the year whether the pump does or not.
- The cost of the water itself, which is free, and the cost of the pump, which belongs on the install page.
- Any tiered, time-of-use, or demand component in your tariff. This uses one flat rate per kWh.
The one sourced money figure on this site
The default electricity rate comes from the United States Energy Information Administration's Electric Power Monthly. In EIA's July 2026 issue, Table 5.6.A, the U.S. Total row shows 18.44 cents per kilowatt-hour for residential customers in May 2026 (transcribed from the table, not a sentence EIA wrote), which is $0.18 per kilowatt-hour. EIA prints this note with the table:
Values are preliminary estimates based on a cutoff model sample.
Read that as the publisher telling you the number is provisional: it is an estimate from a sample, not a final figure. For the decision in front of you a small revision barely registers: a tenth of a cent either way moves the annual total on this page by about $0.10. It matters for a different reason. A figure that arrives with a published caveat about its own sample is not one to buy a pump on without checking, and the check takes a page of your own bill.
| Figure | Value | Label | Source | Date |
|---|---|---|---|---|
| US residential electricity price, May 2026 (preliminary) | 18.44 cents/kWh | sourced | Historical figure from the publisher's archived issue — U.S. Energy Information Administration, Electric Power Monthly, July 2026 issue, Table 5.6.A, May 2026 data, marked preliminary by the publisher: Electric Power Monthly, July 2026 issue (PDF); original retrieval recorded 2026-08-24; that copy was not retained; checked against our saved copy of 2026-10-05. | saved copy 2026-10-05 |
| Converted to dollars | $0.18/kWh | derived | The cents figure divided by 100 | arithmetic |
It is also the wrong number for your house. Residential rates differ by state and by tariff, and this site does not publish state figures, so use the rate on your own bill. Time-of-use tariffs change it again within a day. The national average is here because it is sourced and because a form needs a starting value, not because it describes you.
Measure the watts; do not let us guess them
Running wattage is the other number that decides this calculation. A nameplate figure may not match the running draw at your head; real running watts depend on the motor, on the head it is working against, and on the voltage at the outlet.
| Horsepower band | Assumed running watts | Annual cost at the example duty and rate |
|---|---|---|
| 0.25 HP | 400 W | $9.48 |
| 0.33 HP | 550 W | $13.04 |
| 0.5 HP | 800 W | $18.97 |
| 0.75 HP | 1100 W | $26.08 |
| 1 HP | 1400 W | $33.19 |
Each row keeps the example's same 28 gpm delivered flow and changes only the assumed watts. Across the assumed wattages for every horsepower band, at this duty cycle and this rate, the spread is $23.71 a year ($9.48 to $33.19). On these example inputs that is a weak reason to choose one pump over another; the right flow at your head and a basin that does not force short cycling decide whether the pump does its job.
The cost the calculator above does not show
A backup system's charger draws power every hour of the year whether the pump ever runs or not. It is a small continuous load rather than a large intermittent one, and over 8,760 hours a small continuous load is not necessarily smaller than the pump itself.
We do not model it, because we have no sourced figure for charger standby draw. If you want the number, the same plug-in meter that reads your pump will read the charger, and you can add it here: standby watts multiplied by 8.76 gives kilowatt-hours per year, multiplied by your rate gives dollars.
The reason to mention it at all is honesty about the shape of the answer. When the pump itself costs $17.78 a year on the example inputs, a standby load can be a real share of the total, and a page that quoted only the pump would be understating a system total.
Related tools
- Sizing calculator — the flow-at-head figure this page needs.
- Backup runtime — where the charger and battery actually earn their keep.
- Failure exposure — the other cost to weigh, from your own valuations.
- What genuinely varies by region — this rate against a spread of others, computed the same way.