Quick Answer
The Stihl MS 271 vs 291 choice comes down to about 0.27 horsepower and roughly $90. Both saws weigh 12.3 lbs without bar and chain, use the same .325″ chain, and share the same fuel and oil tank sizes. The MS 291 has a larger 55.5 cc engine and makes 3.76 bhp. The MS 271 has a 50.2 cc engine and makes 3.49 bhp.
Buy the MS 291 if you cut hardwood often or want a 20-inch bar. Buy the MS 271 if you cut mostly firewood and storm cleanup and want to keep the extra money.
Stihl MS 271 vs 291 Specs Side by Side
The Stihl MS 271 vs 291 spec sheets are nearly identical except for the engine. Stihl lists both as gas-powered farm and ranch saws, and both share the same body weight and tank sizes. The engine is where the money goes.
| Spec | Stihl MS 271 Farm Boss | Stihl MS 291 |
|---|---|---|
| Engine displacement | 50.2 cc | 55.5 cc |
| Engine power | 3.49 bhp | 3.76 bhp |
| Powerhead weight | 12.3 lbs | 12.3 lbs |
| Recommended bar | 18 in | 18 in (16 to 20 in offered) |
| Chain | .325″ RM3 | .325″ RM3 |
| Fuel tank | 16.9 oz | 16.9 oz |
| Chain oil tank | 8.12 oz | 8.12 oz |
| Intended use | Farm and ranch | Farm and ranch |
| Typical price (18 in) | About $480 | About $570 |
Two numbers matter most here. The MS 291 engine is about 10.6% larger, but it makes only about 7.7% more power. And because the weight is the same, the extra power comes with no handling penalty.
What Is the Stihl MS 271 Farm Boss?
The Stihl MS 271 Farm Boss is a mid-range gas chainsaw built for firewood, felling small and medium trees, and storm cleanup. It replaced the older MS 270. Stihl says its engine gives 20% longer run times between refuels and cuts exhaust emissions in half compared with that older saw.
It has a pre-separation air filtration system, which spins heavy dust out of the air before it reaches the filter. It also has an anti-vibration system, a side-access chain tensioner, and toolless fuel and oil caps. Dealers sell it with an 18-inch or 20-inch bar.
Use this saw if you want a proven, plain, dependable machine at a fair price. The Farm Boss name has a long track record with farm and property owners.
What Is the Stihl MS 291?
The Stihl MS 291 is a mid-range gas chainsaw with a larger engine than the MS 271, aimed at frequent use around a property. It replaced the older MS 290 and shares the same fuel-saving engine approach and the same 20% run-time claim.
The MS 291 uses the same anti-vibration system, the same side-access chain tensioner, and the same pre-separation air filtration idea. Stihl also offers it in 16-inch, 18-inch, and 20-inch bar lengths. The main change is the bigger cylinder and piston.
Dealers and owners often describe the two as the same saw with a larger engine. The spec sheets back that up.
Engine Power: Does 0.27 bhp Matter?
Yes, but only in the right wood. The MS 291 makes 3.76 bhp against 3.49 bhp for the MS 271. In softwood and small logs, you will not feel much difference. In dense hardwood, or with a longer bar, the 291 holds its chain speed better and bogs down less.
Think of it like towing. A small truck pulls a light trailer fine. The same truck feels strained on a heavy trailer up a hill. The extra horsepower is the headroom you notice only when the load gets heavy.
Where the MS 271 wins:
- It is fully capable of cutting firewood rounds up to about 16 inches thick with an 18-inch bar.
- It costs less to buy, and it uses the same fuel amounts.
- It is the simpler choice if you cut a few cords a year.
Where the MS 291 wins:
- It stays faster through oak, hickory, hard maple, and wet wood.
- It handles a 20-inch bar more comfortably.
- It gives you power in reserve for felling larger trees.
Best for: MS 271 for light to moderate seasonal cutting. MS 291 for people who run the saw for hours at a time.
Weight and Handling: No Penalty for the Bigger Engine
The Stihl MS 271 vs 291 weight comparison is a tie. Stihl lists both powerheads at 12.3 lbs without bar and chain. With an 18-inch bar and chain attached, either saw feels like a mid-size, balanced saw in the 14 to 15 lb range.
Divide weight by power and you get a rough power-to-weight number. The MS 271 carries about 3.5 lbs per bhp. The MS 291 carries about 3.3 lbs per bhp. Lower is better, so the MS 291 gives you slightly more power for every pound you lift.
What this means in the yard:
- Neither saw is tiring on a normal cutting day.
- Both have the same anti-vibration design, so hand fatigue is similar.
- Neither is a good choice for overhead pruning. A lighter top-handle saw is better for that.
Best for: Anyone worried the 291 will be heavier. It is not.
Bar Length and Chain: Where the 291 Pulls Ahead
The Stihl MS 271 vs 291 bar length difference is small on paper and bigger in practice. Stihl recommends an 18-inch bar for the MS 271. The MS 291 is sold with 16-inch, 18-inch, and 20-inch bars.
A longer bar needs more engine to pull the chain through the cut. A 20-inch bar on the smaller engine works, but it cuts slower and the saw works harder. The 291 carries a 20-inch bar with less strain.
Both saws use the same .325″ RM3 chain. An 18-inch bar takes a 74 drive link chain. A 20-inch bar on the 271 needs an 81 drive link chain. This is useful if you already own spare chains, because chains for one 18-inch setup fit the other.
Pros of a longer bar: You can fell thicker trees and cut larger logs in one pass.
Cons of a longer bar: It is heavier at the tip, harder to control, and slower on the smaller engine.
Best for: An 18-inch bar on either saw for general use. A 20-inch bar only on the MS 291.
Fuel, Oil, and Run Time
Both saws hold 16.9 oz of fuel and 8.12 oz of chain oil, so one tank of fuel lasts about as long on either one in similar cutting. Stihl makes the same 20% longer run time claim for both, compared with their older predecessors. It does not claim that one beats the other.
Both run on a 50:1 fuel mix. Stihl recommends non-ethanol, high-octane fuel with premium two-stroke oil. Ethanol fuel left in the tank over winter causes more carburetor trouble than any other single factor I see on the repair bench.
What worked on both: Fuel and oil caps open without tools, and the caps stay attached so you do not lose them in sawdust.
Trade-off: The tanks are small. You will refuel often on a full day of cutting. This is true of both saws.
Best for: Anyone who wants a saw that is easy to refuel quickly in the field.
Maintenance and Shared Parts
The MS 271 and MS 291 share the same air filter, which makes upkeep simple if you own both or switch later. Their chain, bar, and many wear parts are interchangeable too. This lowers your long-term parts cost.
The pre-separation air filtration system on both saws spins out large dust before it reaches the filter. Stihl says this doubles the time between filter cleanings. Even so, clean the filter whenever you see dust build up, and always before long cutting sessions.
Basic upkeep is the same on both:
- Sharpen the chain often. A dull chain makes any saw feel weak.
- Clean or replace the air filter when it clogs.
- Replace the spark plug once a year if you use the saw heavily.
- Keep the bar groove clean and flip the bar now and then to even out wear.
- Drain or stabilize fuel before storing the saw for the off-season.
A dull chain on a 291 cuts slower than a sharp chain on a 271. Sharpening matters more than the extra 0.27 bhp.
Best for: Owners who want low-fuss, repeatable upkeep on either saw.
Starting and Everyday Use
Both saws start with a pull cord and use Stihl’s single-lever control for choke and run settings. Both have a side-access chain tensioner, so you can adjust chain tension from the side with a bar wrench instead of reaching under the cover.
The MS 291’s higher compression can make the pull feel a little firmer. Owners often mention that, though it varies by saw and by how well it is tuned. A fresh spark plug and a clean air filter help a lot on both.
Both saws are built in the United States using US and global components, according to dealer product pages.
Stihl MS 271 vs 291 Price and Value
The price gap in the Stihl MS 271 vs 291 comparison is about $90 for an 18-inch saw. The MS 271 typically sells for about $480. The MS 291 typically sells for about $570. Prices may vary by retailer and change over time.
Here is how the extra $90 breaks down:
| Cost view | MS 271 | MS 291 |
|---|---|---|
| Typical 18 in price | About $480 | About $570 |
| Extra power | Base | +0.27 bhp |
| Cost per bhp | About $138 | About $152 |
| Weight | 12.3 lbs | 12.3 lbs |
You pay about 19% more for about 7.7% more power. That is a poor deal if you rarely push the saw. It is a fair deal if you cut hard wood weekly, because the time you save adds up over a season.
Value verdict: The MS 271 is the better value on paper. The MS 291 is the better saw for heavy use. If $90 does not matter to your budget and you want headroom, buy the 291. If it does matter, the 271 will do the job.
Which Saw Fits Your Yard? Choose by Situation
The right Stihl MS 271 vs 291 pick depends on how much you cut and what you cut. Match the saw to your real workload, not the biggest number on the spec sheet.
| Your situation | Best pick | Why |
|---|---|---|
| Small yard, a few downed limbs a year | MS 271 | Lower price, plenty of power |
| 2 to 5 cords of firewood a year | MS 271 | Handles typical rounds well |
| 5 or more cords a year | MS 291 | Extra power saves time and strain |
| Mostly oak, hickory, or other hardwood | MS 291 | Holds speed in dense wood |
| Storm cleanup in the South or Midwest | Either | Both clear fallen limbs and small trees |
| Want a 20-inch bar | MS 291 | Bigger engine pulls the longer bar |
| Tight budget | MS 271 | Saves about $90 |
| First chainsaw, light use | MS 271 | Simple, proven, and affordable |
If you cut for a living all day, neither is the right tool. Stihl’s own professional line, such as the MS 261, offers more power, a lighter powerhead, and tougher parts for full-time work.
Features Both Saws Share
Because the two saws share so much, most features you read about apply to both. Here is what you get either way:
- An anti-vibration system that reduces hand fatigue.
- A pre-separation air filtration system for longer filter life.
- A side-access chain tensioner for quick adjustment.
- Toolless fuel and oil caps with retainers.
- A throttle trigger interlock as a safety feature.
- Polymer housings that are light and resist corrosion.
- A reduced-emission engine that Stihl says gives 20% longer run times than its predecessors.
If a feature sounds like a reason to choose one over the other, double-check it. It probably belongs to both.
Features You Can Skip Paying For
If you are cutting a few cords a year, you do not need the MS 291’s extra displacement. You also do not need a 20-inch bar on either saw for ordinary firewood. An 18-inch bar cuts rounds up to about 16 inches across in one pass and keeps the saw easier to control.
Pay for extra power only if your cutting habits demand it. A good chain, a sharp file, and a clean air filter will improve your cutting more than another 0.27 bhp.
Common Buying Mistakes
These are the mistakes I see most often when people choose between these two saws:
- Buying on cc alone. The MS 291 has 10.6% more displacement, but only 7.7% more power. Look at bhp and weight, not just cc.
- Choosing a 20-inch bar on the 271. The smaller engine works harder and cuts slower. Stay at 18 inches.
- Assuming the 291 is heavier. Stihl lists the same 12.3 lb powerhead weight for both.
- Ignoring fuel quality. Ethanol fuel left in the tank is the top cause of hard starting. Use fresh mix.
- Skipping safety gear. Chaps, eye protection, hearing protection, gloves, and boots are not optional.
- Buying a pro-duty job on a farm saw. For daily commercial cutting, look at Stihl’s pro line.
- Paying more for the bigger saw, then running a dull chain. Sharpening beats horsepower.
Maintenance and Long-Term Cost
Over several years, the cost of owning either saw is mostly chains, fuel, oil, filters, and spark plugs. The saws themselves use the same wear parts, so your ongoing costs are about the same.
Here is a rough yearly picture for a homeowner who cuts about 3 to 5 cords:
| Cost item | Typical use |
|---|---|
| Chain sharpening or a new chain | One to two chains a year |
| Air filter | Clean often, replace as needed |
| Spark plug | Replace yearly |
| Fuel and two-stroke oil | Depends on hours used |
| Bar wear | Replace after several chains |
Because the parts are shared, one set of spares covers both saws. If you upgrade from a 271 to a 291 later, your chains, filters, and many parts carry over.
Recommended Specs by User Type
Use this table to match the saw and setup to your needs.
| User type | Saw | Bar length | Notes |
|---|---|---|---|
| Light homeowner | MS 271 | 18 in | Best value |
| Regular firewood cutter | MS 291 | 18 in | Extra power for hardwood |
| Property owner felling larger trees | MS 291 | 20 in | Only on the larger engine |
| Budget buyer | MS 271 | 18 in | Saves about $90 |
| Daily commercial user | Stihl pro line | Varies | Beyond farm and ranch class |
Frequently Asked Questions
What is the difference between the Stihl MS 271 and MS 291?
The main difference is the engine. The MS 291 has a 55.5 cc engine making 3.76 bhp. The MS 271 has a 50.2 cc engine making 3.49 bhp. Weight, tank sizes, and chain type are the same on both saws.
Is the Stihl MS 291 more powerful than the MS 271?
Yes, by about 0.27 bhp, which is roughly 7.7% more power. You notice it most in dense hardwood and with longer bars. In softwood and light cutting, the two feel very close.
Is the MS 291 heavier than the MS 271?
No. Stihl lists a 12.3 lb powerhead weight for both saws. The MS 291 gives you more power for the same weight, which improves its power-to-weight ratio slightly.
Can the MS 271 run a 20-inch bar?
Yes, dealers sell it with a 20-inch bar, and it needs an 81 drive link chain. But Stihl recommends an 18-inch bar for the MS 271. The smaller engine cuts slower with the longer bar. The MS 291 handles a 20-inch bar better.
Do the MS 271 and MS 291 use the same parts?
Many parts are shared, including the air filter and the .325″ RM3 chain type. Check the part number for your exact saw and bar length before you buy. A dealer can confirm the fit in a minute.
Is the extra $90 for the MS 291 worth it?
It is worth it if you cut hardwood often, run a 20-inch bar, or use the saw for hours at a time. It is not worth it for a few light jobs a year. In that case, the MS 271 does the work and saves you money.
Is the MS 291 a professional chainsaw?
No. Stihl classes both saws as farm and ranch saws, not full-time professional saws. For all-day commercial use, Stihl points to its pro models, such as the MS 261.
What fuel mix do these saws use?
Both use a 50:1 fuel mix. Stihl recommends non-ethanol, high-octane fuel with premium two-stroke oil. Mix fresh fuel and avoid leaving it in the tank for months.
Final Buying Advice
The Stihl MS 271 vs 291 decision is simple once you know how you cut. Choose the MS 271 for light to moderate firewood and cleanup at the lower price. Choose the MS 291 for hardwood, heavy seasons, or a 20-inch bar. Either way, you get the same weight, the same tanks, and the same dependable Stihl build.
Why Trust This Guide
Siddik Kazi runs a lawn mower and small-engine repair service in Italy, so the maintenance and parts advice here comes from real workshop experience. This guide was put together from the manufacturer’s published specifications, dealer product listings, and a review of how owners describe both saws. Where a number is a MowerInsights calculation, such as cost per bhp, it is labeled as one.