Scag SFC-21
Push / Walk-Behind mower · Model SFC-21 · Commercial-duty · Gas
$1,699–$2,049 Scag list price (configurations)
Manufacturer list price only — it excludes tax, freight, dealer setup and any local discount, and dealers set the final price.
- Mows an acre in 120 min (84 at top speed) How long for your yard? ›
- How these are worked out ›
The Scag SFC-21 is a commercial-grade gas walk-behind mower, built for daily professional use, with a 21-inch deck and a 163cc engine making 4 hp. It weighs 136 lb (61.7 kg).
At a glance
Compare similar mowers See how this mower compares with machines of a similar size and purpose.
Few close matches: the list also allows a wider deck range, other duty classes and discontinued models, each labelled.
Chosen by stated rules, not opinion: same class, a deck within 2 in of this one, the same kind of power and a compatible duty class, then the closest power, weight and price, with other makers preferred. Figures are the manufacturers’ published ones; nothing is estimated.
Engine
| Power Source | gas |
|---|---|
| Displacement | 9.9 ci (163 cc) |
| Engine Power | 4 hp |
| Cylinders | 1 |
| Engine Make | Honda |
Deck
| Cutting Width | 21 in (533 mm) |
|---|---|
| Min Cut Height | 1.5 in (38 mm) |
| Max Cut Height | 4.5 in (114 mm) |
| Deck Construction | 14 gauge deck with 14-gauge replaceable guards for strength and longevity. Deep draw stamped. |
Drive
| Ground Speed | 4.2 mph |
|---|---|
| Transmission | GT MG 512 transmission, 3-speed |
Dimensions
| Weight | 136 lbs (61.7 kg) |
|---|---|
| Fuel Capacity | 0.4 gal (1.4 L) |
Similar models
Other push / walk-behind mowers with comparable specs — including other brands — that buyers cross-shop with the SFC-21.
Specs verified against the manufacturer spec sheet on Jun 6, 2026 — scag.com.
See every mower with a Honda engine ›
What the parts on this spec sheet mean
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Independent reference database. Specs compiled from manufacturer sources and normalized for comparison; verify with the manufacturer or dealer before purchase.
What the specs work out to
Figures MowerFacts computes from Scag’s own numbers — not published by the manufacturer.
Mowing time
- ¼ acre30 min 21 min
- ½ acre1 h 42 min
- 1 acre2 h 1 h 24 min
- 2 acres4 h 1 min 2 h 48 min
About 120 min per acre at 0.5 acres/hour, mowing at 2.9 mph. The second figure is at the published 4.2 mph top speed (0.71 acres/hour) — faster than anyone really mows. About 0.2 acres per tank.
Gate & trailer fit
- 32 in gateFits
- 36 in gateFits
- 48 in gateFits
Needs at least 27 in of clearance (estimated).
Power & run time
- Power per deck inch0.191 hp/in
- Run time per tank~0.4 h
Mowing times assume 0.5 acres/hour: deck width x 2.9 mph at 80% efficiency, which allows for overlap, turns and trimming. 2.9 mph is 70% of the 4.2 mph top speed Scag publishes - almost nobody mows flat out. The "at top speed" figure is the same sum at 4.2 mph, shown so you can see it.
Fit uses the deck width plus 6 in for the discharge chute, because Scag doesn't publish an overall width — measure before buying if a gate is tight.
Run time assumes a typical 1 gal/hour burn at working load; real consumption varies with engine, load and cut.
Scag SFC-21 questions
What size deck is on the Scag SFC-21?
The Scag SFC-21 has a 21-inch (533 mm) cutting deck.
What engine is in the Scag SFC-21?
The Scag SFC-21 is powered by a Honda, 163 cc, 4 hp. Horsepower is the manufacturer's own rating.
How much does the Scag SFC-21 weigh?
The Scag SFC-21 weighs 136 lb (61.7 kg) as specified by Scag.
How fast is the Scag SFC-21?
Top ground speed is 4.2 mph. With its 21-inch deck that works out to about 0.71 acres per hour at 80% efficiency — allowing for overlap, turns and trimming.
How long does the Scag SFC-21 take to mow an acre?
About 1 h 25 min per acre, from its 21-inch deck at 4.2 mph and 80% efficiency — roughly 0.71 acres an hour, so five acres is about 7 h 3 min. Rough or obstacle-heavy ground takes longer; this is deck width times ground speed, not a timed test.
How big is the fuel tank on the Scag SFC-21?
The Scag SFC-21 holds 0.4 gal (1.4 L) of fuel.
How much does the Scag SFC-21 cost?
Scag's published list price is $1,699 to $2,049 depending on configuration, checked 22 October 2026. That excludes tax, freight, dealer setup and any local discount — dealers set the final price.
What is the Scag SFC-21 built for?
Commercial-duty push / walk-behind mower. Built for daily, paid commercial use.
Source: Scag (manufacturer) · archived copy