7 Best 21 Inch Lawn Mowers to Buy in 2025

The WORX Nitro 40V isn’t just another cordless mower—it’s a game-changer for eco-conscious homeowners tired of gas fumes and pull-cord struggles. With its brushless motor 2.0, this electric beast delivers 40% more power than prior-gen models, slicing through thick grass with precision. The real star? Aerodeck Technology, which supercharges airflow under the deck to prevent clumping and boost mulching efficiency—making it a top-tier performer for clean, even cuts on lawns up to half an acre. Say goodbye to clogged decks and uneven discharges; this mower tackles moisture-heavy grass like a pro.

In real-world testing, the dual 20V 5.0Ah PowerShare batteries delivered consistent runtime, easily handling 0.4-acre yards on a single charge. The IntelliCut sensors dynamically adjust blade speed based on grass density—ramping up in tall patches and down in thinner zones—extending battery life without sacrificing cut quality. Transitioning between mulching, bagging, and side-discharge is tool-free and intuitive, while the 7-position height lever (1.5″–4″) ensures adaptability across seasons. However, on steep slopes or dense overgrowth, the motor occasionally hesitated, revealing its limits in extreme conditions.

When stacked against the PowerSmart 80V, the WORX trades some raw runtime for smarter energy management and a more refined cutting system. Compared to gas models like the BILT HARD 201cc, it wins on ease of use and emissions, though it lacks self-propelled drive. Ideal for suburban homeowners with moderate-sized lawns, this mower blends cutting-edge tech with user-friendly design—delivering premium performance with zero cords or fuel. It’s not the most powerful, but it’s the smartest-balanced package for eco-friendly, low-maintenance mowing.

If effortless mowing across sprawling lawns is your priority, the BILT HARD 21-inch self-propelled mower is a muscular, no-nonsense workhorse built for endurance. Its 201cc 4-cycle OHV engine generates 9.0 ft·lb of torque, effortlessly powering through wet, tall grass without bogging down. The rear-wheel drive and single-speed self-propel transform what’s usually a chore into a smooth stroll—ideal for uneven terrain or sloped yards where push mowers struggle. Add in the no-choke, no-primer start, and you’ve got a mower that fires up instantly, every time.

Out in the field, this machine shines on larger properties (0.5+ acres), where its 21-inch steel deck slashes mowing time with each pass. The 8-position height adjustment (1.2″–3.75″) is a standout, offering finer tuning than most competitors—perfect for precise seasonal cuts or low-mow enthusiasts. Rear bagging collects clippings efficiently, while mulching chops them fine for healthy lawn return. That said, the collection bag fills quickly in dense grass, and the lack of variable speed means you’re locked into one forward pace, which can feel sluggish on small lawns.

Against the PowerSmart self-propelled model, this BILT HARD offers more torque and better height granularity, though both share similar deck designs. Compared to cordless options like the WORX Nitro, it sacrifices convenience for raw power and all-day runtime. Best suited for homeowners with large, challenging lawns who value reliability over quiet operation, this mower delivers professional-grade performance without the pro price—outmuscling most in its class while staying remarkably user-friendly.

The AMERISUN 21-inch gas mower is a budget-savvy standout that refuses to cut corners on core performance. Don’t let the price fool you—its 140cc OHV engine delivers smooth, vibration-free starts and consistent power across moderate-sized lawns. The 2-in-1 functionality (mulching and side discharge) keeps things simple and effective, making it perfect for homeowners who prioritize reliability over bells and whistles. With 7″ front and 10″ rear wheels, it glides over bumps and curbs without getting stuck—ideal for uneven or rocky terrain.

During testing, the mower handled small to medium yards (up to 0.3 acres) with ease, though frequent stops were needed for emptying clippings when side-discharging. The 6-position dual-lever height adjustment (1.5″–3.9″) works well, but requires adjusting each wheel individually—a slight hassle compared to single-lever rivals. The foldable handle is a major win, slashing storage footprint by nearly 50%, and the included engine oil means it’s ready to mow right out of the box. However, it lacks rear bagging, which limits versatility for those who prefer clippings collection.

Pitted against the BILT HARD 201cc, it trades power for affordability and compactness. Compared to the PowerSmart 3-in-1 models, it misses the bagging option but wins on price and storage efficiency. For first-time homeowners or renters with modest yards, this mower delivers solid performance without overspending—proving you don’t need premium features to get a clean, dependable cut. It’s the most value-packed entry-level 21-inch mower in the lineup.

When versatility and brand reliability top your list, the PowerSmart 21-inch mower with Briggs & Stratton engine steps up as a trustworthy all-rounder built to last. Powered by a 140cc B&S engine, known for its smooth ignition and rock-solid durability, this mower starts reliably in all conditions and maintains steady RPMs even in thick grass. The 3-in-1 functionality (bag, mulch, rear discharge) is flawlessly executed—switching modes is fast and tool-free—making it ideal for dynamic lawn care routines across seasons.

In real-world use, the 1.4-bushel bag holds a decent amount, reducing emptying frequency, while the brushless deck design ensures even mulching with minimal clumping. The single-lever 6-position height adjustment (1.5″–3.9″) is intuitive and consistent, and the 10″ rear wheels with rear-wheel drive provide excellent grip on inclines. However, the self-propel mechanism requires constant handle pressure, which can tire hands over long sessions. On flat lawns, it’s smooth sailing; on rough terrain, it demands more user input than top-tier self-propelled models.

Versus the BILT HARD 201cc, it offers slightly less torque but matches it in cutting width and functionality. Compared to the WORX Nitro, it wins on runtime and power but loses on noise and emissions. Best for homeowners seeking a dependable, multi-mode mower for medium to large yards, this PowerSmart model balances performance, ease of use, and brand trust—delivering consistent results year after year. It may not be flashy, but it’s the workhorse you can count on when the grass grows tall.

The PowerSmart 80V 21-inch cordless mower is a silent powerhouse that brings gas-level cutting performance without the mess or noise. Running on an 80V MAX 6.0Ah battery, it delivers up to 40 minutes of runtime—enough to tackle 0.5-acre lawns on a single charge. The brushless motor and all-steel deck ensure long-term durability, while the button-start system eliminates pull-cord frustration. With 3-in-1 functionality and a 6-position height lever (1.6″–4″), it’s as flexible as any gas model, making it a top pick for larger, eco-focused yards.

In testing, the mower maintained strong blade speed even in damp, dense grass, thanks to the high-voltage system. The rear bag, mulch, and side-discharge modes all performed cleanly, with minimal clogging—a testament to the deck design. However, once the battery dipped below 20%, power noticeably dropped, and recharging takes ~2 hours, so overlapping large mows isn’t feasible. While lightweight for its class, the lack of self-propel makes it a workout on uneven terrain.

Stacked against the WORX Nitro 40V, this PowerSmart offers double the voltage and longer runtime, but lacks smart features like IntelliCut. Compared to gas mowers like the BILT HARD, it wins on ease of use and maintenance but can’t match endless runtime. Ideal for homeowners with large yards who want a clean, quiet, high-performance alternative to gas, this mower delivers pro-level results with minimal upkeep. It’s the most powerful cordless option here, built for those who refuse to compromise.

For those crunched on space but unwilling to sacrifice performance, the 21-inch Steel Deck Gas Mower is a storage-savvy powerhouse that’s ready to mow in minutes. This unit arrives fully assembled—just unfold the handle and go—saving time and frustration. The auto-choke 144cc OHV engine starts reliably with minimal pulls, while the forced air-cooling system keeps it running cool during extended sessions. With a 21-inch steel deck and 3-in-1 functionality, it handles bagging, mulching, and side discharge with equal finesse, making it a versatile pick for seasonal lawn care.

On the lawn, it delivers consistent, clean cuts across flat to moderately uneven terrain. The 6-position single-lever height adjustment (1.5″–3.9″) is smooth and synchronized, and the 10-inch rear wheels with double ball bearings ensure smooth rolling. But the real standout is the foldable design—it collapses vertically, fitting neatly in garages, sheds, or even apartments with limited storage. The 1.4-bushel bag fills quickly, and no battery or charging means you’re never down due to power loss.

Compared to the AMERISUN model, it adds rear bagging and easier height adjustment. Against the PowerSmart B&S version, it matches features but wins on setup speed and storage. Perfect for urban homeowners, townhouse dwellers, or anyone with tight storage, this mower proves convenience and performance can coexist. It’s not flashy, but it’s the smartest choice when space is at a premium—offering full-size cutting in a compact, ready-to-go package.

The BILT HARD 21-inch 201cc gas mower is a precision-focused performer that shines where cutting height flexibility matters most. With an industry-leading 8-position single-lever adjustment (1.2″–3.75″), it offers finer control than nearly any other 21-inch model, making it ideal for golf-course-style grooming or seasonal transitions. Its 201cc OHV engine delivers 9.0 ft·lb of torque, ensuring strong blade speed even in thick patches, while the no-choke, single-pull start gets you mowing in seconds.

In real-world use, the mower powers through medium to large lawns with consistent performance, and the 3-in-1 functionality works seamlessly—mulching finely, bagging efficiently, and side-discharging cleanly. The 9.5″ rear wheels with double ball bearings roll smoothly over rough terrain, and the foam-wrapped handle reduces vibration and fatigue. However, as a push-only model, it demands more effort than self-propelled rivals, especially on inclines or wet grass.

When compared to the BILT HARD self-propelled version, it sacrifices drive assist for a lower price and lighter frame. Against the PowerSmart 3-in-1, it offers more height options and stronger engine output. Best for homeowners who prioritize lawn aesthetics and precise mowing heights, this mower is a detail-oriented tool for those who treat their yard like a canvas. It may not have self-propel, but it’s the best choice when cutting precision is non-negotiable—delivering barber-level control with workhorse reliability.