Pool Pump Energy Cost Calculator

Energy cost is a short chain from watts to kilowatt-hours (kWh) to dollars. First we resolve your pump's power to watts, then convert daily energy and multiply by your electricity rate.

power → watts:
  watts mode:      effectiveWatts = watts
  horsepower:      effectiveWatts = HP × 746      (estimate — see note)
  amps × volts:    effectiveWatts = volts × amps  (most accurate label path)

energy + cost:
  dailyKwh    = (effectiveWatts / 1000) × hoursPerDay
  dailyCost   = dailyKwh × rate
  monthlyKwh  = dailyKwh × 30.4          (avg days/month = 365 ÷ 12)
  monthlyCost = dailyCost × 30.4
  annualKwh   = dailyKwh × 365 × (seasonMonths / 12)
  annualCost  = dailyCost × 365 × (seasonMonths / 12)

Month basis = 30.4 days (365 ÷ 12), not a flat 30, so that monthly × 12 equals the annual figure exactly — a flat 30 makes twelve months only 360 days, undercounting the year by about 1.4%. Some calculators use × 30; on the example above that lands ~$77/mo versus our ~$78/mo. The season length multiplies the annual figure only — a 6-month season roughly halves the year — while the day and month figures describe an operating day and month.

Horsepower is an estimate. The HP → watts path uses 1 HP ≈ 746 watts, but nameplate horsepower overstates the real electrical draw of a pool pump. When you can, read amps × volts off the motor label, or use a measured watt reading — both are more accurate than nameplate HP.

Where the preset rates come from. A rate ships as a preset here only when we can read it off the page of the body that publishes it — a regulator or a statistical agency — never off a vendor blog or a comparison site. That is the whole differentiator: most pump-cost pages quote a rate nobody can trace. Today that means three markets. The US preset is the residential average in the EIA's Electric Power Monthly Table 5.6.A (18.44¢/kWh, May 2026). The UK preset is Ofgem's own default-tariff cap unit rate for Direct Debit customers (26.11p/kWh for 1 July–30 September 2026, including 5% VAT). The Australian presets are the Victorian Default Offer domestic flat-rate usage charges set by the Essential Services Commission, one per distribution zone, for 1 July 2026–30 June 2027. Markets where we could not read a per-kWh figure off the publisher's own page get no preset at all — use your bill instead.

Standing charges are deliberately excluded. Ofgem's cap and the Victorian Default Offer both pair a unit rate with a fixed daily charge (57.19p/day and $1.19–$1.38/day respectively). You pay those whether the pump runs or not, so adding them would inflate what the pump itself costs. This tool prices the marginal energy the pump uses. Each preset is stamped with the period it covers and the date we read it; a preset never silently outlives its published period, and a rate you type by hand is labelled as your own, never attributed to a regulator. Picking a market switches the display currency so the symbol matches the source — it never converts money between currencies.

This tool gives your pump's current running cost. To weigh a variable-speed upgrade — annual savings, premium, and payback years — use the Variable-Speed Pump Savings Calculator. To cost the other big draw on a pool, the Pool Heater BTU Calculator sizes heating demand.

Sources: U.S. Energy Information Administration — Electric Power Monthly, Table 5.6.A; Ofgem — energy price cap unit rates and standing charges; Essential Services Commission (Victoria) — Victorian Default Offer; EnergyBot — Pool Pump Energy Calculator; ElectricianCalc — Pool Pump Cost Calculator; SolarTech — Pool Pump Electricity Usage. Full links below.