Greenworks 40V 20" Brushless Cordless Lawn Mower with 4.0Ah Battery & Charger(75+ Tool Compatibility) Review

Overview

The Greenworks 40V 20" Brushless Cordless Lawn Mower is a solid mid-range electric option designed for homeowners with small to medium-sized lawns—think quarter-acre or less. It pairs a 20-inch cutting deck with a brushless motor and a 4.0Ah battery, aiming to deliver gas-like performance without the fumes, noise, or maintenance headaches. This mower is best for those who want a reliable, lightweight machine that’s easy to store and start, especially if you’re already invested in the Greenworks 40V tool ecosystem.

Who Should Buy This

• Homeowners with 1/4 acre or smaller lawns: The 4.0Ah battery gives you about 30-45 minutes of runtime, which is enough for a typical suburban yard without needing a second battery. If your grass is under 6 inches and not overly thick, this mower will handle it in one charge.
• Buyers transitioning from gas mowers: If you’re tired of dealing with stale gas, oil changes, and pull cords that never cooperate, this is a painless switch. It starts instantly with a push button, and the brushless motor means no belts or brushes to replace.
• Homeowners who value tool compatibility: Greenworks’ 40V platform includes over 75 tools—trimmers, blowers, chainsaws, and more. If you already own a Greenworks 40V battery, you can use it here, saving money and storage space.
• Seniors or those with limited mobility: At around 40 pounds (battery removed), this mower is noticeably lighter than most gas models. The self-propelled version is optional, but even the push model is easy to maneuver, and the handle folds for compact storage.

Key Features Breakdown

• 20-inch cutting deck: This is a sweet spot for small to medium lawns. It’s wide enough to cut efficiently—fewer passes than an 18-inch mower—but narrow enough to fit through standard gates and maneuver around flower beds. The steel deck is durable but adds a bit of weight; still, it feels solid, not flimsy.
• Brushless motor: Unlike brushed motors, this one has no carbon brushes to wear out, so it lasts longer and runs cooler. It also delivers more torque, which means better performance in slightly damp or tall grass. You’ll notice it doesn’t bog down as easily as cheaper cordless mowers.
• 4.0Ah battery and charger: The 40V, 4.0Ah battery is a decent size for this class. Expect 30-45 minutes of runtime on a full charge, depending on grass thickness and height. The charger takes about 60-90 minutes to fully recharge, which is average. If your lawn is on the larger side, you’ll want a second battery.
• 75+ tool compatibility: This is a major selling point. The battery works with Greenworks’ entire 40V lineup—trimmers, blowers, hedge trimmers, chainsaws, and even a snow thrower. If you already own Greenworks tools, you’re set. If not, it’s a smart entry into a versatile system.
• Push-button start and variable speed: No pull cords, no priming. Just press a button and squeeze the bail handle to go. The variable speed trigger lets you adjust pace—useful for thick patches or when you need to slow down near obstacles.
• Single-lever height adjustment: Seven positions from 1.25 to 3.5 inches, adjustable with one lever. It’s simple and quick, though not as refined as some premium models with individual wheel adjustments. Still, it works fine for most lawns.
• Side discharge, mulching, and rear bagging: You get three options. The mulching plug is included and does a decent job chopping clippings fine enough not to clump. The rear bag is a bit small (about 1.5 bushels), so you’ll need to empty it more often on larger lawns. Side discharge is good for tall grass but can leave a trail.

Pros

• Instant start with no gas or oil: Push-button ignition is a game-changer. No winterizing, no carburetor cleaning, no fuel stabilizer. Just charge and go.
• Quiet operation: At around 75 decibels, it’s significantly quieter than gas mowers. You can mow early morning or late evening without annoying the neighbors.
• Lightweight and easy to store: At about 40 pounds, it’s easy to lift into a shed or car trunk. The folding handle reduces storage footprint to roughly 2 feet tall.
• Good torque from brushless motor: Handles thick grass and slight inclines better than many cordless mowers in this price range. It doesn’t stall out easily.
• Ecosystem compatibility: If you already own Greenworks 40V tools, this mower is a no-brainer. If not, it’s a solid entry point into a wide range of outdoor power equipment.
• Decent build quality for the price: The steel deck feels sturdy, and the plastic components are well-fitted. It’s not pro-grade, but it’s not flimsy either.

Cons

• Limited runtime on a single charge: 30-45 minutes is enough for a small lawn, but if your grass is thick or tall, you might run out before finishing. A second battery is almost essential for anything over 1/4 acre.
• Bag capacity is small: The rear bag fills up quickly, especially with damp or thick grass. You’ll be stopping to empty it frequently, which can be annoying.
• Self-propelled version is not available in all markets: This review covers the push model. If you have a sloped lawn or prefer self-propelled, you’ll need to look at the Greenworks 40V self-propelled variant, which costs more.
• Plastic components feel less durable over time: The chute and some handle parts are plastic. They hold up fine for normal use, but if you’re rough on equipment or hit rocks often, you may see cracks or wear.

Bottom Line

The Greenworks 40V 20" Brushless Cordless Lawn Mower is a strong choice for homeowners with small to medium lawns who want a reliable, low-maintenance electric mower. It delivers solid cutting performance, starts instantly every time, and fits into a versatile tool ecosystem. The runtime is the main limitation—if your lawn is over 1/4 acre or very thick, plan on buying a second battery or stepping up to a dual-battery model. For the price, it’s a well-built machine that will save you from gas, oil, and noise headaches. I’d recommend it confidently for suburban yards, especially if you’re already a Greenworks 40V user.

Frequently Asked Questions

Q: How long does the battery last, and can I use a larger battery from the Greenworks 40V line?
A: The included 4.0Ah battery lasts about 30-45 minutes under