PowerSmart B8721S1 Self-Propelled

Last updated: October 31, 2026

PowerSmart B8721S1 Self-Propelled
3.4/5#14 of 22 in self-propelled lawn mowers
3.4

A low cost rear wheel drive mower with a name brand engine, for sloped lawns up to a third of an acre that you bag or mulch.

  • 21 inDeck
  • 140 cc (Briggs & Stratton E550)Power
  • Rear-wheel driveDrive
Check price at Amazon$389.99Check price at PowerSmart$379.99

Price checked October 31, 2026. As an Amazon Associate we earn from qualifying purchases.

Pros
  • Rear wheel drive for slopes at a budget price
  • Briggs & Stratton engine that most repair shops can service
  • Single lever height adjustment
Cons
  • No side discharge for overgrown grass
  • No published warranty term
  • Single speed drive cannot slow down for tight spots

The PowerSmart B8721 family

Every PowerSmart B8721 model we rank, smallest first. Ratings compare each against its own drive.

ModelDeckRatingPrice
PowerSmart B8721P Push20 in3.2/5$349.99
PowerSmart B8721S1 Self-Propelled (this one)21 in3.4/5$379.99

How it scores

The rating comes from 5 measured or published factors, each scored 0-100 against fixed reference points for its drive. How we rank explains each one.

Specifications

Model numberB8721S1
Cutting
Deck width21 in
DeckSteel
Cutting height1.5 to 3.9 in, 6 positions
BagYes
Bag capacity1.7 bushels
MulchYes
Side dischargeNo
Power
PowerGas
Engine or battery140 cc (Briggs & Stratton E550)
Electric startNo
Build
DriveRear-wheel drive
Weight70 lb

Alternatives in this drive

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