Lawn mowers are the most visible noise in a suburban weekend and the least documented in the US market. Of the makers we checked, only Husqvarna prints a mower noise figure on a US product page. The rest of what is known comes from the same makers' European pages and manuals, where EU law requires the numbers.
Twelve battery walk-behind mowers sold in the US carry maker declarations. At the operator they run from 79 to 85 dB(A) among firm matches; guaranteed sound power runs from 93 to 98.
The same mowers, different disclosure
STIHL sells its battery mowers in the US under the same names it uses in Europe: RMA 448 V, RMA 453 PV, RMA 765 V and others. Its US pages print no sound data. Its UK and Australian pages print the operator figure, the uncertainty value and the guaranteed sound power in their technical details, and its European manual for the RMA 765 V adds the standard, EN IEC 62841-4-3, and a measured sound power.
EGO prints nothing in the US and declares fully in its European manuals under EU model numbers. We match those to US mowers by the specs both manuals print, and label each match. The LM2135SP match is exact: blade speed, bag, all eight cutting heights and weight agree. Weaker matches stay out of the picks.
Gas is closer than you think
STIHL declares its gas RM 655 V at 84 dB(A) at the operator and a guaranteed 98 dB(A). That is the same operator figure as its big battery RMA 765 V and the same guaranteed power as its battery RMA 756 V. On chainsaws and trimmers, battery tools undercut gas by 15 dB(A) or more in the same maker's paperwork; on mowers, by STIHL's own numbers, the gap under load is a few decibels at most.
The declarations suggest the blade and deck, not the motor, make much of a mower's cutting noise. Battery mowers still win outright at idle, at startup and between passes, and they produce no exhaust. But a buyer expecting a mower that cuts in near silence should read the figures first.
Two numbers, never one ranking
Each mower carries two quantities: LpA at the operator position, and LWA, the sound power the mower puts into the neighborhood, with a guaranteed ceiling. We rank on the operator figure and show guaranteed power beside it, as in our string trimmer guide. The sound power vs sound pressure explainer covers why.
Husqvarna's consumer LE-322R page lists a guaranteed 98 dB(A) beside a measured sound power of 66 dB(A). A measured value 32 decibels under its guaranteed ceiling is not credible, so we use only the 98. Milwaukee's EU page for its M18 dual battery mower declares the lowest operator figure we found, 75.8 dB(A), but it lists three different sound power values and the US 2823-20 is a probable rather than confirmed twin. EGO's Australian manuals print sound figures in the 60s that match nothing else EGO publishes, and we ignored them.
The silent aisle
Honda and Toro publish no mower noise figure in the US manuals and pages we checked, and Husqvarna's gas W520 page leaves its sound fields empty. For quiet mowing that is rarely a question of noise at all, see our robot mower guide.
We did not measure any of these mowers. Every figure is the maker's own, quoted as published, with the standard, K value and source identified wherever the maker identified them.
