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Best 21 Inch Lawn Mower Under $400 (2026): 5 Picks Compared

Five 21-inch push lawn mowers under $400 with four gas models and one battery model compared by engine or battery, deck modes, cutting heights, wheel sizes and warranty terms.

Best 21 Inch Lawn Mower Under $400 (2026): 5 Picks Compared
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Top picks at a glance

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  1. 1SENIX LSPG-M14Best OverallSENIX LSPG-M149.5/10View on Amazon
  2. 2PowerSmart 40V MB2400BBest BatteryPowerSmart 40V MB2400B9.5/10View on Amazon
  3. 3PowerSmart DB8621CBest 2-in-1 GasPowerSmart DB8621C9.4/10View on Amazon
  4. 4BILT HARD 201ccMost Cutting HeightsBILT HARD 201cc9.4/10View on Amazon
  5. 5SENIX 21" 144cc Gas Push Lawn MowerSENIX 21" 144cc Gas Push Lawn MowerView on Amazon
  6. 6BLACK+DECKER Electric Lawn MowerBLACK+DECKER Electric Lawn MowerView on Amazon
  7. 7LawnMaster MEB1114K Electric Corded Lawn Mower 15-Inch 11AMPLawnMaster MEB1114K Electric Corded Lawn Mower 15-Inch 11AMPView on Amazon
  8. 8BLACK+DECKER Electric Lawn Mower with Bike HandleBLACK+DECKER Electric Lawn Mower with Bike HandleView on Amazon
  9. 9LawnMaster Electric Lawn Mower 12AMP 19-Inch ME1218X.01LawnMaster Electric Lawn Mower 12AMP 19-Inch ME1218X.01View on Amazon

Maintaining a residential lawn or property perimeter up to an acre requires a dependable walk-behind mower that can handle mixed turf, weed patches and fence lines without bogging down. For property owners working within a strict price cap, finding the best 21 inch lawn mower under 400 means balancing engine displacement or battery capacity against deck build quality and wheel size. The five push mowers evaluated below include four gas models and one 40V cordless unit, compared strictly on manufacturer specifications with missing data marked.

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Quick picks

  • Best Overall SENIX LSPG-M14: Highest Acre Score here: 144cc engine, 3-in-1 deck with 1.7-bushel bag, 11-inch rear wheels and a 2-year warranty Check price on Amazon
  • Best Battery PowerSmart 40V MB2400B: 40V brushless motor, two 4.0Ah batteries, steel deck and 2-year service Check price on Amazon
  • Best 2-in-1 Gas PowerSmart DB8621C: 144cc engine, 2-in-1 mulch and side-discharge, foldable handle and a 2-year warranty Check price on Amazon
  • Most Cutting Heights BILT HARD 201cc: Stated 201cc engine, 10 cutting positions and 9.5-inch rear wheels Check price on Amazon

Our acreage picks

SENIX LSPG-M14 21-Inch 144cc Gas Push Lawn Mower

SENIX LSPG-M14 21-Inch 144cc Gas Push Lawn Mower

SENIX9.5/10 Acre Score
i
The Acre Score (out of 100, shown as /10) weighs rated performance, build, value, safety listing and warranty. How we score

Gas push mower with a 21-inch steel deck, a 144cc OHV engine, 3-in-1 mowing with a 1.7-bushel bag, 11-inch rear wheels and a 2-year warranty.

Who it's for: homeowners with yards up to 1 acre who want a lightweight gas mower with full 3-in-1 bagging versatility and larger rear wheels.

Who should skip it: anyone mowing steep banks who needs self-propelled drive or those seeking battery power.

Read the full review

The SENIX LSPG-M14 features a 144cc 4-cycle OHV engine delivering 3.4 HP and 5.8 ft-lb of torque, pre-filled with engine oil. Its 21-inch steel deck handles mulching, side discharge and rear bagging with an included 1.7-bushel grass catcher. Dual levers set 6 cutting heights from 1.25 to 3.75 inches, rolling on 8-inch front and 11-inch rear wheels. The listing includes a 2-year limited warranty and states a weight of 54.2 pounds. A contradiction appears between the spec table, which lists 8-inch wheels and stainless steel, and the bullets, which cite 11-inch rear wheels and a steel deck.

Pros

  • 2-year limited warranty stated on the listing
  • Full 3-in-1 capability with a 1.7-bushel grass bag included
  • 11-inch rear wheels paired with 8-inch front wheels for rougher ground
  • Lightweight gas push mower at 54.2 lb

Cons

  • Spec table lists wheel size as 8 inches while bullets state 11-inch rear wheels
  • Spec table lists material as stainless steel while bullets state a steel deck
  • Push drive requires manual effort on slopes
  • No safety bail or operator presence controls are stated in the listing
PowerSmart MB2400B 40V 21-Inch Cordless Lawn Mower

PowerSmart MB2400B 40V 21-Inch Cordless Lawn Mower

PowerSmart9.5/10 Acre Score
i
The Acre Score (out of 100, shown as /10) weighs rated performance, build, value, safety listing and warranty. How we score

Battery push mower with a 21-inch steel deck, two 40V 4.0Ah batteries, brushless motor, 2-in-1 mulch and bag, and a 2-year service term.

Who it's for: owners of smaller properties up to 1/4 acre who want quiet mowing without mixing gas or maintaining a combustion engine.

Who should skip it: property owners with more than 1/4 acre or anyone needing a side discharge chute.

Read the full review

The PowerSmart MB2400B is a 40V cordless push mower with a brushless motor, a 21-inch steel deck and two 40V 4.0Ah batteries with a charger included. The listing rates runtime for up to 1/4 acre on two packs or 1/8 acre on one pack. A single lever adjusts cutting height across 6 positions from 1.5 to 3.9 inches, supporting mulching and rear bagging with an included grass collection bag. Weight is 56.4 pounds, and the listing states a 2-year service term and lifetime technical support. The spec table lists the manufacturer as Amerisun Inc.

Pros

  • Includes two 40V 4.0Ah batteries and a charger with quick-swap design
  • Brushless motor runs quieter than gas engines
  • 2-year service and lifetime tech support stated on the listing
  • Steel 21-inch deck rather than plastic

Cons

  • Rated for yards up to 1/4 acre on two batteries
  • 2-in-1 mowing only, with no side discharge option
  • Listing spec table names Amerisun Inc as manufacturer rather than PowerSmart
  • No safety certifications or operator presence controls are stated
PowerSmart DB8621C 21-Inch 144cc Gas Push Lawn Mower

PowerSmart DB8621C 21-Inch 144cc Gas Push Lawn Mower

PowerSmart9.4/10 Acre Score
i
The Acre Score (out of 100, shown as /10) weighs rated performance, build, value, safety listing and warranty. How we score

Gas push mower with a 21-inch steel deck, a 144cc 4-cycle OHV engine, 2-in-1 mulch and side discharge, and a 2-year warranty.

Who it's for: homeowners maintaining flat residential lawns who prefer mulching or side discharge without the bulk of a grass bag.

Who should skip it: anyone who wants to bag clippings or navigate rough ground on small 7-inch wheels.

Read the full review

The PowerSmart gas push mower features a 144cc 4-cycle OHV engine with recoil start and auto choke, paired with a 21-inch steel deck. It offers 2-in-1 mulching and side discharge, with a single lever providing 6 height settings from 1.5 to 3.9 inches. It rolls on 7-inch wheels, weighs 59 pounds and includes a foldable handle for compact storage. The listing states a 2-year limited warranty in its spec table. Note that the listing title names the model DV8621C, whereas the spec table designates it as DB8621C.

Pros

  • 2-year limited warranty stated in the spec table
  • Single-lever 6-position height adjustment from 1.5 to 3.9 inches
  • Foldable handle design for compact garage storage
  • Arrives 95 percent assembled per the listing

Cons

  • Model number is listed as DV8621C in title but DB8621C in spec table
  • 2-in-1 mulching and side discharge only, with no rear bagging option
  • Small 7-inch wheels across front and rear
  • Weight of 59 lb is heavier than the SENIX gas mower
BILT HARD 201cc 21-Inch Gas Push Lawn Mower

BILT HARD 201cc 21-Inch Gas Push Lawn Mower

BILT HARD9.4/10 Acre Score
i
The Acre Score (out of 100, shown as /10) weighs rated performance, build, value, safety listing and warranty. How we score

Gas push mower with a 21-inch steel deck, a 201cc 4-stroke engine, 10 cutting positions and 9.5-inch rear wheels.

Who it's for: buyers who want a heavier steel deck, ball-bearing wheels and wide height adjustment for varied lawn conditions.

Who should skip it: anyone requiring a stated manufacturer warranty or lightweight maneuverability.

Read the full review

The BILT HARD push mower is presented with a 201cc 4-stroke OHV engine rated at 9.0 ft-lb of torque in the title and bullets, built on a 21-inch 3-in-1 steel deck. A synchronized single lever controls 10 height settings from 1.2 to 3.75 inches, rolling on 8-inch front and 9.5-inch rear ball-bearing wheels. Weight is 73.8 pounds. Several sharp contradictions exist in the listing: the spec table lists a 144cc 3.8 HP engine and 8 height positions rather than 201cc and 10 positions, and marks the collection bag with an X despite claiming bagging. No concrete warranty term is stated.

Pros

  • Stated 201cc 4-stroke engine delivers 9.0 ft-lb of torque in bullets
  • Synchronized single-lever height adjustment offers 10 positions from 1.2 to 3.75 inches
  • Large 9.5-inch rear and 8-inch front double ball-bearing wheels
  • 3-in-1 steel deck for bagging, mulching and side discharge

Cons

  • Spec table contradicts title and bullets, listing a 144cc 3.8 HP engine and 8 positions
  • Spec table lists collection bag with an X despite title claiming rear bagging
  • No warranty term is stated on the listing
  • Heaviest mower here at 73.8 lb
AMERISUN AV8621C1 21-Inch 144cc Gas Push Lawn Mower

AMERISUN AV8621C1 21-Inch 144cc Gas Push Lawn Mower

AMERISUN9.3/10 Acre Score
i
The Acre Score (out of 100, shown as /10) weighs rated performance, build, value, safety listing and warranty. How we score

Gas push mower with a 21-inch steel deck, a 144cc OHV engine, 2-in-1 mulch and side discharge, and a foldable handle.

Currently unavailableCheck price on Amazon

Who it's for: homeowners with simple suburban lawns who want a basic 2-in-1 gas mower with a foldable handle.

Who should skip it: anyone who needs a grass catcher bag, large rear wheels or a stated warranty.

Read the full review

The AMERISUN AV8621C1 is powered by a 144cc 4-stroke OHV engine on a 21-inch steel deck configured for mulching and side discharge. A single lever adjusts cut height through 6 positions between 1.5 and 3.9 inches, and the handle folds for garage storage. Weight is listed at 63 pounds. The listing does not state wheel dimensions, nor does it provide a stated warranty term or mention a rear bagging kit.

Pros

  • 144cc 4-stroke OHV engine with recoil start
  • Single-lever height adjustment across 6 positions from 1.5 to 3.9 inches
  • Steel 21-inch cutting deck
  • Foldable handle for seasonal storage

Cons

  • No warranty term is stated on the listing
  • Wheel diameter is not stated in title, bullets or spec table
  • 2-in-1 only, lacking a rear grass collection bag
  • Weighs 63 lb, which is heavier than other 144cc mowers here

Other machines to compare

Side-by-side specs

Model Acre Score Power Engine or battery Cutting width Deck modes Cutting heights Warranty
SENIX LSPG-M14 9.5/10 Gas 144cc 4-cycle OHV 21 in 3-in-1 (mulch, bag, side discharge) 1.25 to 3.75 in 2 years limited
PowerSmart 40V MB2400B 9.5/10 Battery 40V, 2 x 4.0Ah 21 in 2-in-1 (mulch, bag) 1.5 to 3.9 in 2 years service
PowerSmart DB8621C 9.4/10 Gas 144cc 4-cycle OHV 21 in 2-in-1 (mulch, side discharge) 1.5 to 3.9 in 2 years limited
BILT HARD 201cc 9.4/10 Gas 201cc 4-stroke OHV 21 in 3-in-1 (mulch, bag, side discharge) 1.2 to 3.75 in Not stated
AMERISUN AV8621C1 9.3/10 Gas 144cc 4-stroke OHV 21 in 2-in-1 (mulch, side discharge) 1.5 to 3.9 in Not stated

Specifications are manufacturer rated as listed, collected 13 October 2026.

Acreage and terrain fit

SENIX LSPG-M14

Acreage fitUnder 11-22-55-1010+
Terrain fitFlatRough ground

PowerSmart 40V MB2400B

Acreage fitUnder 11-22-55-1010+
Terrain fitFlat

PowerSmart DB8621C

Acreage fitUnder 11-22-55-1010+
Terrain fitFlat

BILT HARD 201cc

Acreage fitUnder 11-22-55-1010+
Terrain fitFlatRough ground

AMERISUN AV8621C1

Acreage fitUnder 11-22-55-1010+
Terrain fitFlat

Buying guide: best 21 inch lawn mower under 400

Gas vs cordless battery power

The four gas push mowers in this roundup run on 4-cycle or 4-stroke OHV engines, with 144cc units on the SENIX, PowerSmart DB8621C, and AMERISUN, and a stated 201cc engine on the BILT HARD. These engines run on standard automotive gasoline without fuel mixing. The PowerSmart 40V MB2400B operates with a brushless electric motor and two 40V 4.0Ah battery packs, rated by the manufacturer for up to 1/4 acre on two packs and 1/8 acre on one pack. Cordless power eliminates spark plug upkeep, motor oil and pull starting, while gas engines offer continuous mowing capability across larger yard sessions.

2-in-1 vs 3-in-1 cutting deck versatility

A 21-inch cutting deck provides a broad swath for residential grass, but deck discharge options vary across these models. The SENIX LSPG-M14 and BILT HARD 201cc provide 3-in-1 decks that support mulching, side discharge, and rear bagging, with the SENIX package supplying a 1.7-bushel grass bagger. The PowerSmart DB8621C and AMERISUN AV8621C1 are 2-in-1 models designed for mulching and side discharge without a collection bag. The PowerSmart 40V cordless unit supports mulching and rear bagging with an included bag, omitting side discharge. For advice on circulating clippings under the deck, read our guide on lawn mower blades for mulching.

Cutting heights and adjustment levers

Managing lawn height across growing seasons depends on available deck settings. The SENIX LSPG-M14 provides 6 cutting heights from 1.25 to 3.75 inches using dual levers. The PowerSmart models and the AMERISUN mower provide 6 positions ranging from 1.5 to 3.9 inches via a single lever. The BILT HARD listing claims a 10-position synchronized single lever spanning 1.2 to 3.75 inches, though its spec table contradicts this by listing 8 positions. Single-lever mechanisms adjust all wheels simultaneously, saving time compared to multi-lever systems.

Wheel diameter and property terrain

Wheel dimensions heavily influence how easily a manual push mower rolls across uneven turf, ruts and small depressions. The SENIX model features 8-inch front wheels and 11-inch rear wheels, while the BILT HARD unit features 8-inch front wheels and 9.5-inch rear wheels with ball bearings. Larger rear wheels roll over lawn bumps with less operator effort. In contrast, the PowerSmart DB8621C uses 7-inch wheels, which are better suited for smooth, level lawns. AMERISUN does not state wheel dimensions. To understand standard deck widths and footprints, review our guides on push lawn mower sizes and walk-behind mower sizes.

Slopes and mowing safety

None of the manufacturer listings publishes an official slope rating. When operating a manual push mower on sloping ground, always walk across the slope face rather than up and down to prevent slipping toward the spinning blade. Operators should wear eye and hearing protection, and clear sticks, stones and wire debris from the lawn before beginning. For gas units, always shut down the engine and allow it to cool completely before refueling outdoors.

Use our slope measurement guide to check steep ground.

Slope Calculator

Turn rise and run, or a phone level reading, into degrees and percent, then compare it with typical mower slope ratings.

Open the calculator
Walk-behind and brush mower safety

Walk the area first and clear stones, sticks, wire and toys. Wear eye and hearing protection, long pants and sturdy closed footwear, mow across slopes with a walk-behind (not up and down), and never pull a running mower toward you. Keep kids and pets well away. Refuel only with the engine off and cool. See CPSC lawn mower safety. Read our Safety Disclaimer.

Matching It to Your Property

  • Flat lawns up to 1/4 acre: The PowerSmart 40V MB2400B battery push mower suits compact, flat properties where quiet brushless operation is desired, rated for up to 1/4 acre on two 40V 4.0Ah battery packs.
  • Rougher or uneven residential turf: The SENIX LSPG-M14 and BILT HARD 201cc provide larger rear wheels (11 inches and 9.5 inches respectively) that navigate bumps and molehills more easily than smaller 7-inch push mower wheels.
  • Yards with heavy grass accumulation: The SENIX LSPG-M14 provides a full 3-in-1 steel deck with a stated 1.7-bushel grass bag, allowing neat collection when tall growth cannot be cleanly mulched or side discharged.
  • Tight shed and garage storage: The AMERISUN AV8621C1 and PowerSmart DB8621C feature foldable handle designs that reduce overall storage footprint in compact utility sheds.

The Acre Score explained

The Acre Score evaluates five key criteria: performance (engine displacement or battery voltage, cutting width, and deck flexibility), build quality (deck material, wheel construction, and dry weight), value (features delivered relative to stated specifications), safety (operator presence bail, blade brake, and electrical certifications), and warranty (stated coverage duration and terms). When a manufacturer listing omits a specification or warranty term, that category receives zero points.

Product Acre Score Perf. /35 Build /25 Value /25 Safety /10 Warranty /5
SENIX LSPG-M14 9.5 30 20 21 0 3
PowerSmart 40V MB2400B 9.5 28 20 21 0 4
PowerSmart DB8621C 9.4 27 19 20 0 3
BILT HARD 201cc 9.4 28 18 19 0 0
AMERISUN AV8621C1 9.3 27 18 18 0 0

Scores run from 9.2 to 9.8: each product’s point total is placed on that range, so more points always means a higher score.

FAQ: mowing large lots

Is a 21-inch push mower suitable for an acre of lawn?

A 21-inch push mower can mow properties up to an acre, but because it relies on manual push effort rather than self-propelled drive, mowing a full acre requires significant physical walking time. Many owners use a 21-inch push model for trimming around fences, garden beds and tight obstacles while maintaining larger open acreage with a riding mower.

What is the difference between 2-in-1 and 3-in-1 lawn mowers?

A 2-in-1 mower offers two grass disposal methods, typically mulching and side discharge (or mulching and bagging). A 3-in-1 mower includes mulching, side discharge, and rear bagging capabilities with a dedicated collection bag, offering maximum flexibility across different seasons and grass conditions.

Can a 40V battery mower match a 144cc gas push mower?

A 40V cordless mower with a brushless motor delivers sufficient cutting performance for routine residential turf and eliminates fuel mixing, exhaust and oil changes. However, runtime on the included two 4.0Ah battery packs is manufacturer rated for up to 1/4 acre, whereas a 144cc gas engine runs continuously as long as fuel is supplied.

How often should mower blades be sharpened on a 21-inch deck?

Keeping blades sharp ensures clean grass cuts and reduces strain on smaller 144cc gas engines and cordless motors. See our guide on how often to sharpen mower blades and our tips on how to clean a mower deck after mowing.

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