The standard size for many walk-behind mowers. A sharp, balanced blade here is crucial for a professional-quality cut. But when it’s time for a replacement, choosing the right 21 inch lawn mower blade can feel confusing. You’ve got mulching blades, high-lift options, and basic cutting blades all claiming to be the best. We’re here to cut through the noise and help you find the perfect match for your grass and mower.
Think about your lawn’s needs. Do you want finer clippings, better bagging, or just a clean, even cut? The wrong blade can leave stragglers and put extra strain on your engine. Let’s look at what makes a great blade and which features are actually worth you’re money.
Product Comparison Table: 9 Best 21 Inch Lawn Mower Blade
| Image | Why We Like This Product | Editor’s Rating | |
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UDC Parts 942-0741A Mower Blades 21 Inch Replacement for…
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9.6 |
Read Review |
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Grasscool TB110 Mulching Blade for Troy Bilt 21 inch…
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9.4 |
Read Review |
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Hipa 942-0741A Mulching Blade for Troy Bilt 21 inch…
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9.2 |
Read Review |
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Maxpower 331528B Mulching Blade for some 21 Inch Cut…
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9.1 |
Read Review |
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Grasscool 942-0741A Mulching Blades for Troy Bilt 21 inch…
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8.9 |
Read Review |
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MaxPower 331737B Mulching Blade for Many 21 in. Cut…
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8.7 |
Read Review |
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SWAPARTS Lawn Mower Blade for Greenworks 21 inch Mower…
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8.5 |
Read Review |
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Grasscool 406712 532406712 Mower Mulching Blade with Circle Mounting…
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8.4 |
Read Review |
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Grasscool 21 inch Mulching Blade for Troy Bilt Cub…
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8.2 |
Read Review |
Quick Review For Top 9 21 Inch Lawn Mower Blade
UDC Parts 942-0741A Mower Blades 21 Inch Replacement for Troy Bilt TB130 TB240 TB160 TB115 TB230 Craftsman M230 M250 Cub Cadet Yard Machines 742-0741 742-0741A 942-0741 CMXGZAM100067 / Mulching 2 Pack
The UDC Parts 942-0741A Mower Blades are a 21-inch replacement set designed to restore the cutting performance of your walk-behind lawn mower. This two-pack of mulching blades directly replaces a wide range of original equipment manufacturer (OEM) part numbers, including common ones like MTD 942-0741A, 742-0741, and Craftsman CMXGZAM100067, among many others listed.
If your old blades are worn, bent, or no longer providing a clean cut, these are formulated to be a direct fit substitute.
Precise dimensions are crucial for safe and effective operation. These blades measure 21 inches in length (measured diagonally), with a width of 2-1/4 inches and a thickness of 0.126 inches. The center hole is a bow-tie shape, with a 5/16 inch side hole, and they are designed for compatible 21-inch cutting decks.
The air lift design of 1-7/64 inches helps with grass dispersal and bagging, while the 6-7/64 inch cutting edge is where the work gets done. Its important to verify these measurements against your current blades before installation.
Compatibility is extensive, covering many popular brands and models. These blades are confirmed to fit a long list of Troy-Bilt models like the TB115, TB130, TB160, TB230, and TB240.
Grasscool TB110 Mulching Blade for Troy Bilt 21 inch Deck Mower TB240 TB230 TB130 TB200 TB160 TB210 TB280ES TB320 TB115 TB220 21" Walk Behind Push Mower Replace 942-0741A 742-0741A
The Grasscool TB110 Mulching Blade is a direct replacement part designed specifically for a wide range of Troy Bilt 21-inch walk-behind mowers. If your mower model is a TB110, TB130, TB200, TB210, TB230, TB240, TB280ES, TB320, or several others listed, this blade is built to fit.
It officially replaces OEM part numbers 942-0741A, 742-0741A, and many other common variants, so you can be confident in its compatibility for your machine.
This is a true 3-in-1 blade, meaning it handles mulching, bagging, and side-discharging all with one piece of hardware. Its design focuses on creating a strong airflow that lifts grass for a clean cut and then finely shreds the clippings.
For mulching, those numerous curves cuts and re-cuts the grass into tiny pieces that fall back onto your lawn, acting as a natural fertilizer to nourish the soil. If you prefer bagging, the blade’s high-lift design is noted to improve bagging capacity significantly, potentially by up to 50%, which means less stopping to empty the bag.
Hipa 942-0741A Mulching Blade for Troy Bilt 21 inch Lawn Mower, TB110 TB240 TB230 TB130 Lawn Tractor,Craftsman Yard Machine MTD Murray 21 inch Deck Riding Mower (After 1995)
The Hipa 942-0741A Mulching Blade is a direct replacement part designed to restore the performance of your 21-inch lawn mower. If your current blade is dull, damaged, or simply not mulching effectively, this blade provides the specifications and compatibility you need for a clean cut.
This blade is built to match original equipment manufacturer (OEM) standards, with part numbers like CC-742-0741, 742-0741A, and 942-0741.
Its primary fit is for a wide range of Troy Bilt models, including the popular TB110, TB130, TB230, and TB240 lawn tractors. However, its compatibility extends much further. It is engineered to work with many 21-inch deck mowers (produced after 1995) from brands like Craftsman, MTD, Murray, Yard Machines, and Snapper.
Always double-check your mower’s model number and existing blade length before ordering to ensure a proper fit.
The key specification are a blade length of 21 inches, a width of 2-1/4 inches, and a center hole in a “bow tie” shape. It’s constructed from a durable alloy steel that incorporates chromium and molybdenum for enhanced strength and better resistance to wear and rust compared to standard blades.
Maxpower 331528B Mulching Blade for some 21 Inch Cut MTD/Cub Cadet/Troy-Bilt Replaces 742-0741, 942-0741, CMXGZAM100067
The Maxpower 331528B Mulching Blade is a direct replacement part designed for a wide range of popular 21-inch lawn mowers. If your mower is from brands like MTD, Cub Cadet, Troy-Bilt, or Craftsman, this blade is likely the correct fit to restore your machine’s mulching performance. Its primary job is to finely chop grass clippings and redeposit them onto your lawn, acting as a natural fertilizer and eliminating the need for bagging.
This can save you time and effort while giving your lawn valuable nutrients.
Before ordering, the most critical step is to verify compatibility. You must match the OEM part number from your current or original blade to the extensive list this product replaces. Compatible numbers include 742-0741, 942-0741, and Craftsman CMXGZAM100067, among several others listed in the features. Checking this number is the only way to insure a proper and safe fit for your specific mower deck.
Do not rely solely on mower model names.
This blade fits an extensive list of Cub Cadet models, including many in the CC Series like the CC 46M, CC 469, and CC 999ES, as well as SC Series models such as the SC 100, SC 300, and SC 700 H. It also fits numerous Troy-Bilt models, from the TB 105 and TB 130 up to the TB 490 XP, along with various Tru-Cut, Tuff Cut, and Pro-Cut series.
Grasscool 942-0741A Mulching Blades for Troy Bilt 21 inch Deck Mower TB110 TB230 TB240 TB130 TB210 TB320 TB220 TB280ES 21" Walk Behind Push Mower Replace 742-0741A 942-0741
The Grasscool 942-0741A Mulching Blade is a direct replacement part designed for a wide range of popular Troy-Bilt and Craftsman walk-behind mowers. If your mower model is listed, this blade is engineered to fit precisely and restore your machine’s cutting performance. Its crucial to verify the compatibility details before you order to ensure a smooth installation process.
This blade is specifically made for mowers with a 21-inch deck and a Bow Tie spindle pattern.
The center hole shape is a key detail; this blade will only fit spindles that match that Bow Tie design. Please double-check your current blade’s center hole against the product images or your mower manual. The blade dimensions are Length: 21 inches, Width: 2-1/4 inches, and Thickness: 9/64 inches, with a lift height of 1-1/8 inches.
Functionally, this is a versatile 3-in-1 blade. It handles mulching, bagging, and side-discharging effectively.
The design features numerous curves that create a strong airflow. This lifts the grass for a clean cut and then recuts the clippings into very fine pieces. For mulching, these tiny pieces decompose quickly, returning valuable nutrients back to your soil and promoting a healthier lawn.
MaxPower 331737B Mulching Blade for Many 21 in. Cut Craftsman, Husqvarna, Poulan Mowers, Replaces OEM no. 165833, 175052, 406712, 532175064, 594893001, 175064
The MaxPower 331737B Mulching Blade is a direct replacement part designed for a wide range of popular 21-inch lawn mowers. If your Craftsman, Husqvarna, or Poulan mower is due for a new blade, this could be the exact fit you need. Its primary job is to finely chop grass clippings and return them to your lawn as a natural fertilizer, which can help improve soil health and reduce the need for bagging.
Compatibility is the key feature here.
This single blade replaces a long list of original equipment manufacturer (OEM) part numbers, including common ones like 165833, 175052, 406712, 532175064, and 594893001. We’ve included the full list in the product details, but its always a good idea to double-check. Before you order, please take a moment to verify the OEM number from your old blade or your mowers owner manual matches one of the numbers listed for this item.
This simple step ensures you get the right part and avoids any hassle with returns. We also see it fits models like the Craftsman CMXGZAM100129.
The blade has a standard 5/8-inch center hole diameter, which is common for many walk-behind mowers. It’s manufactured right here in the USA to meet or exceed all original specifications.
SWAPARTS Lawn Mower Blade for Greenworks 21 inch Mower C3208101 MO40L4413, MO40L03, MO48L4422
The SWAPARTS Lawn Mower Blade for Greenworks 21 inch Mower C3208101 MO40L4413, MO40L03, MO48L4422 is a direct replacement part designed to get your mower cutting like new again. If your current blade is dull, bent, or damaged, this is the part you need to restore a clean and even cut to your lawn. It’s crucial to ensure a proper fit for safety and performance, so please compare your old lawn mower blade with our pictures before ordering.
This blade is specifically engineered for compatibility with Greenworks models C3208101, MO40L4413, MO40L03, and MO48L4422.
This blade measures 20.08 inches in length, 1.97 inches in width, and has a thickness of 0.67 inches. These precise dimensions are what makes it a perfect fit for your specific mower deck. Using a blade with incorrect dimensions can lead to poor cutting results, vibration, and even damage to your mower.
So double-checking those model numbers is the most important step you can take.
Constructed from a single piece of sturdy steel, this blade is built for durability and efficiency. The one-piece design means there are no weak points or joints that could fail under stress. This robust construction helps the blade resist wear and tear, allowing it to stay sharper for longer compared to lesser quality blades.
Grasscool 406712 532406712 Mower Mulching Blade with Circle Mounting Pattern for Craftsman Husqvarna 21 inch Deck Push Walk Behind Lawnmower Replace 165833 175064 189028 532189028
The Grasscool 406712 (532406712) Mower Mulching Blade is a direct replacement part designed for specific 21-inch walk-behind mowers. Its crucial to understand this blade features a specific Circle Mounting Pattern center hole. This is the most important detail to check before you buy, as compatible mower brands use different patterns.
If you have a Craftsman 21″ deck push mower, you need to identify your original blades center hole shape. This Grasscool blade has a Circle Hole.
If your original Craftsman blade has a Bow Tie shaped center hole, this blade will not fit. You would need to look for a part with MPN 942-0741A instead. The same careful check applies to Husqvarna 21″ deck push mowers. This blade is only compatible if your Husqvarna’s original blade has a Circle Hole.
If your Husqvarna blade has a 5-Star shaped center hole, you should search for MPN 580258102 to find the correct replacment.
This mulching blade is built to commercial specifications for durability and performance. It measures 21 inches in length, 2-1/4 inches in width, and has a thickness of 5/32 inch. The design includes a 1-1/8 inch air lift wing, which helps create a strong vacuum to stand grass up for a clean cut and improves mulching efficiency by recutting clippings.
Grasscool 21 inch Mulching Blade for Troy Bilt Cub Cadet 742p0741-x 742-0741 942-0741A 942-0741-X SC500E SC500Z SC700E CC989 Walk-Behind Push Self-Propelled Mowers
The Grasscool 21 inch Mulching Blade is a direct replacement part designed for a wide range of popular walk-behind mowers. If your current blade is worn, damaged, or simply not mulching effectively anymore, this blade aims to restore your mower’s cutting performance. Its primary function is to finely chop grass clippings so they can decompose back into your lawn, acting as a natural fertilizer.
This can help reduce the need for bagging and promotes a healthier turf.
Compatibility is the key feature of this blade. It is manufactured to replace original part numbers 742p0741-x, 742-0741, 942-0741A, 942-0741-X, and several others from Cub Cadet, MTD, and Troy Bilt. It fits 21-inch cutting decks on many push and self-propelled mowers made from 1995 onward.
Beyond the primary brands, it also compatible with models from Craftsman, Bolens, White Outdoor, Murray, Snapper, Yard Machines, Yard-Man, and Huskee that use those specific OEM numbers. Always verify your original blade’s specifications before ordering.
The list of compatible mower models is extensive. For Cub Cadet, it includes the CC989, SC500E, SC500Z, SC700E, CC469, and numerous SC/CC series models.
21 Inch Lawn Mower Blade Buying Guide
Replacing a 21-inch blade requires an exact match for fit, balance, and cutting style. It’s not just about length; teh center hole and mounting pattern must align perfectly with your mower’s deck. Getting the right one means a safer, smoother cut and protects your machine from damaging vibrations.
Material & Durability
Not all steel is created equal. You’ll typically find blades made from standard carbon steel or hardened, high-carbon steel. The latter holds a sharp edge much longer and resists bending or nicking when it hits an unseen rock or root. Think of it as the difference between a disposable razor and a quality kitchen knife. Investing in a tougher material saves you time and money on frequent replacements.
Blade Design & Cut Quality
Do you want a pristine, striped lawn or just a tidy cut? Standard straight blades are great for basic mulching and bagging. For a finer, salon-quality finish, look for a “lift” or “high-lift” design. These have curved wings that create stronger airflow, standing the grass up for a cleaner cut and improving bagging performance. Some blades are specifically engineered for mulching, with extra curves to chop clippings into tiny pieces that nourish your lawn.
Compatibility is Key
This is the most crucial step. Your mower’s model number is your best friend here. It’s usually on a sticker on the deck or near the engine. Cross-reference this number with the blade manufacturer’s compatibility chart. Never guess based on length alone! Also, note the shape of the center hole—is it a star, a circle, or a hexagon? An incorrect fit is a major safety hazard and won’t work properly.
Ease of Installation
If you’re doing this yourself, check if the new blade comes with a hardware kit. Having the correct new bolts and washers (which are often a special “star” lock pattern) is essential for a secure fit. Remember to disconnect the spark plug before you start, and use a block of wood to wedge the old blade while loosening the bolt. A little prep makes the whole job quick and safe.
Frequently Asked Questions About 21 Inch Lawn Mower Blade
How do I know if my mower takes a 21 inch blade?
Check your mower’s manual first. If you don’t have it, you can measure the old blade. Remove it safely and measure from tip to tip. A true 21 inch blade will measure close to 21 inches across. Some mowers list the cutting width on the deck itself.
Are all 21 inch blades the same?
No, they are not. The main difference is the center hole and mounting pattern. You must match these to your specific mower model. Using the wrong blade can be dangerous and won’t fit properly. Always cross-reference the part number.
What’s the difference between a standard and a high-lift blade?
A standard blade is good for general mowing. A high-lift blade has a more curved design. It creates stronger suction to stand grass up for a cleaner cut and better bagging. They’re great if you bag your clippings often.
How often should I replace my mower blade?
You should inspect it a few times each season. Look for nicks, cracks, or a dull edge. Most blades need sharpening or replacement once a year with normal use. A dull blade tears grass, which can turn it brown.
Can I sharpen the blade myself?
Yes, you can if you have the right tools and follow safety steps. Always disconnect the spark plug first. You’ll need a file or grinder to sharpen it evenly. If the blade is badly damaged or out of balance, it’s safer to just replace it.
Is it hard to change the blade?
It’s a straightforward job. You’ll need a wrench to loosen the bolt holding the blade on. The main trick is blocking the blade from spinning. A piece of wood works good for this. Remember to wear gloves and disconnect the spark plug wire before you start.
Why does blade balance matter?
An unbalanced blade causes vibration. This vibration puts extra stress on your mower’s engine and spindle. Over time, it can lead to premature wear or damage. Always check balance after sharpening or install a new, pre-balanced blade.
The Final Call
A sharp, correctly fitted blade is essential; these options ensure a clean, healthy cut for your specific mower model. Choosing teh right one means your mower works efficiently, saving you time and effort. Your lawn will look better, and the grass will be healthier because it’s cut cleanly instead of being torn. Remember, a dull blade stresses your engine and leaves your yard vulnerable to disease. It’s a simple upgrade with a big impact.
Before you make a purchase, double-check your mower’s manual or the old blade itself for the exact specifications. This guarantees a perfect fit and safe operation. Installing a new 21 inch lawn mower blade is a straightforward task that pays off all season long. With the right blade on your mower, you can look forward to a consistently neat lawn without the fuss. Just be sure to disconnect the spark plug first for safety—it’s an easy step that’s to important to skip.