★ EVERYDAY · HOME & GARDEN · COMPARISONS
Electric saves $58.44 a year at the defaults: $71.50 for gas against $13.06 for electric. Enter your mows per week, season length, fuel and electricity prices, and yearly maintenance to see which mower is cheaper to run on your lawn. This is running cost only: the mower itself is not included.
A gas mower burns fuel every mow and needs oil, filters, and a spark plug every year. An electric mower sips kilowatt-hours and mostly needs a blade sharpening. The yearly bill settles it: mows times fuel per mow, priced per gallon or per kilowatt-hour, plus yearly maintenance, for each mower side by side.
At the defaults the gas mower burns 0.30 gallons per mow at $3.50 a gallon, which is $1.05 of fuel per mow, while the electric mower uses 0.60 kWh per mow at $0.17 per kWh, which is $0.10 of electricity per mow — roughly a ten-to-one gap before maintenance is even counted. Over 30 mows a year that is 9.00 gallons and $31.50 of fuel for gas against 18.00 kWh and $3.06 of electricity for electric. Then maintenance widens the gap again: $40 a year for the gas mower's oil, filter, and spark plug against $10 a year for the electric mower's blade sharpening. The totals are $71.50 a year for gas and $13.06 a year for electric, a saving of $58.44 a year. Unlike some comparisons where the winner is a rounding error, this one is not close: electric wins on fuel, wins on maintenance, and wins by more the more you mow.
Season length scales the fuel gap but barely moves the maintenance gap, so electric's lead grows with every extra mow: at 20 mows a year gas costs $61.00 (6.00 gal) against electric at $12.04 (12.00 kWh), a saving of $48.96, while at 40 mows a year gas costs $82.00 (12.00 gal) against electric at $14.08 (24.00 kWh), a saving of $67.92. Price moves the same way: gas at $5.00 a gallon pushes the gas total to $85.00 a year and the saving to $71.94, while electricity at $0.30 per kWh pushes the electric total only to $15.40 a year, leaving a saving of $56.10. The honest flip deserves a plain statement: at the default maintenance levels there is no flip, at any season length, because gas fuel alone costs $1.05 per mow against $0.10 for electric and gas maintenance is $30 a year higher. A flip appears only when electric maintenance climbs well above gas maintenance, and the realistic version of that is a battery replacement: a $150 battery every three years amortizes to about $50 a year, and at just 4 mows a year with gas maintenance of $20 and electric maintenance of $60, gas costs $24.20 a year (1.20 gal) against electric at $60.72 a year (2.40 kWh), so gas saves $36.52 a year. Short seasons plus a battery year are the only honest route to a gas win — and even then it is the battery, not the fuel, doing the work.
Rounding convention, stated plainly: each fuel and energy subtotal is rounded to two decimals, each yearly total is rounded to cents, and the gap is the difference of the rounded yearly totals — so $71.50 minus $13.06 is exactly $58.44, and every branch figure adds up exactly as printed. Rounding is half-up, as in Math.round.
| Output | Formula | What it means |
|---|---|---|
| Mows per year | 1 mow/week × 30 weeks | 30 mows a year at the defaults. |
| Gas fuel per year | 30 mows × 0.30 gal × $3.50 | 9.00 gal, $31.50 of fuel at the defaults. |
| Electric energy per year | 30 mows × 0.60 kWh × $0.17 | 18.00 kWh, $3.06 of electricity at the defaults. |
| Gas total per year | $31.50 fuel + $40 maintenance | $71.50 a year at the defaults. |
| Electric total per year | $3.06 electricity + $10 maintenance | $13.06 a year at the defaults. |
| Yearly gap | Rounded gas total − rounded electric total | $71.50 − $13.06 = $58.44 a year saved by electric at the defaults. |
| Battery-year flip | 4 mows: gas $4.20 + $20 vs electric $0.72 + $60 | Gas $24.20 vs electric $60.72, gas saves $36.52 a year — the only honest flip, and it comes from maintenance, not fuel. |
This is a running-cost model, not a meter reading. It assumes steady fuel and electricity use per mow, while real mows vary with grass height, wetness, and lawn size — a thick spring cut can use noticeably more than a light summer trim on either mower. It excludes the mower purchase price, which is where the real decision often lives: electric mowers can cost more up front, and a battery replacement every few years is a lump sum this yearly model only captures if you enter it as maintenance. It also excludes your time, the value of quieter mowing, and emissions. Measure one real mow — a marked fuel can for gas, a plug-in meter for electric — and enter your own per-mow figures for the most accurate result.
Bright Side Kit. "Gas vs Electric Lawn Mower: Yearly Cost Calculator" https://brightoolbox.com/gas-vs-electric-lawn-mower/ Accessed October 24, 2026.Electric, by a wide margin at the defaults: $13.06 a year against $71.50 for gas, a saving of $58.44 a year.
$71.50 a year at the defaults: 30 mows, 0.30 gallons per mow at $3.50 a gallon ($31.50 of fuel), plus $40 a year of maintenance.
$13.06 a year at the defaults: 30 mows, 0.60 kWh per mow at $0.17 per kWh ($3.06 of electricity), plus $10 a year of maintenance.
Then gas costs $61.00 a year (6.00 gal) and electric $12.04 a year (12.00 kWh), a saving of $48.96 for electric.
Then gas costs $82.00 a year (12.00 gal) and electric $14.08 a year (24.00 kWh), a saving of $67.92 for electric.
No: at $5.00 a gallon gas costs $85.00 a year against electric at $13.06, a saving of $71.94 for electric. The gap grows, the winner stays the same.
Only when electric maintenance climbs well above gas maintenance, as in a battery-replacement year: at 4 mows a year with $20 gas maintenance and $60 electric maintenance, gas costs $24.20 a year against electric at $60.72, so gas saves $36.52 a year. At the default maintenance levels there is no flip at any season length.
The mower purchase price, battery replacement unless you enter it as maintenance, your time, and emissions. It is running cost only, at the figures you enter.