Quick picks: For most hilly yards, the Segway Navimow X430 ($2,499) is the best buy: 40° slope rating, all-wheel drive, wide deck, quiet, and a stable app. If your hill is under trees or beside a tall house, the Mammotion LUBA 3 AWD ($2,399 and up) is the one, because its LiDAR keeps working where GPS drops out. For a small, steep yard, the LUBA mini 2 AWD ($1,999) climbs the same grade for less money. And if your “lawn” is really a rough field with roots and leaves, look at the tracked Lymow One Plus ($2,999).
Everything below explains how we got there, including how to measure your own slope, what actually matters on a hill (it is not just the slope number), and which popular mowers to skip.
First, figure out how steep your yard really is
Every robot mower lists a maximum slope, but manufacturers mix two different units, and that confuses almost everyone.
- Percent grade is rise divided by run. A hill that climbs 1 foot for every 4 feet forward is a 25% grade.
- Degrees is the angle. That same 25% grade is about 14°.
The two scales are not close to each other, which is why an 80% slope sounds like a cliff but is 38.6°, and a 45° slope is a 100% grade. Here are the ratings you will see on spec sheets, converted:
| Percent grade | Degrees | What it feels like |
|---|---|---|
| 20% | 11° | A gentle rolling lawn |
| 30% | 17° | Noticeable hill, fine to walk |
| 45% | 24° | Steep enough to lean into |
| 65% | 33° | Hard to push a mower up |
| 80% | 38.6° | Most people would not walk straight up it |
| 84% | 40° | Same as above, slightly more |
| 100% | 45° | A bank, not a lawn |
How to measure yours: open the compass or measure app on your phone (both iPhone and Android have a level built in), lay the phone flat on a board resting on the steepest part of the lawn, and read the angle. Or use a 4-foot board and a level: lift the downhill end until the bubble centers, measure the gap in inches, and divide by 48. A 12-inch gap on a 48-inch board is a 25% grade.
Then add a safety margin. Buy a mower rated at least 5 to 10 degrees above your steepest section. Ratings are measured on dry grass in good conditions, and your hill will be wet some mornings.
What actually matters on a hill
The slope number gets all the attention, but four other things decide whether a mower will finish your yard or sit at the bottom of it with its wheels spinning.
All-wheel drive. Rear-wheel-drive mowers, which is most mowers under $1,800, lose traction on anything past about 18 to 20 degrees, and sooner when the grass is wet. Every mower in our picks is AWD or tracked. There is no cheap way around this.
Wet grass. Sloped lawns collect runoff, so they stay wet longer than flat ones. Look for a real water-resistance rating (IPX5 or better) and, more important, schedule mowing for the afternoon when the grass has dried.
Cross-slope mowing. Driving across a hill is harder than driving up it. Heavier mowers with wider stances hold a line better. This is where tracked mowers pull ahead of wheeled ones.
Turf damage on turns. This is the problem nobody warns you about. Aggressive AWD tires are great for grip and terrible when the mower gets stuck and spins. Reviewed’s testers found the LUBA 3 “can dig up new and established grass on turns,” and the Dreame A3’s “heavy 4WD tires scalp the lawn fast when stuck.” The Navimow X430 pivots its front wheels instead of dragging them, which is why it came out cleanest in this category. Whatever you buy, mow the hill when it is dry and check the turnaround spots after the first week.
The picks
1. Segway Navimow X430: best for most hilly yards
$2,499 | 84% (40°) | up to 1 acre | AWD | RTK + 360° cameras, no antenna
The X430 has the highest slope rating of any wheeled mower we tested against, and PCWorld found it “crossed slopes and uneven ground without spinning wheels, sliding, or stalling.” Its 17-inch deck is the widest in this group, it cuts anywhere from 0.75 to 4 inches, and at about 60 dB it is the quietest. The front wheels pivot rather than skid, so it is gentler on turns than the Mammotions. Bob Vila named it best overall for 2026.
Skip it if: your hill is under heavy tree cover. The X430 relies on RTK satellite positioning backed by cameras, and dense canopy can cut the signal.
2. Mammotion LUBA 3 AWD: best for hills with trees or shade
$2,399–$2,999 depending on size | 80% (38.6°) | 0.4 to 1.25 acres | AWD | LiDAR + RTK + cameras
The LUBA 3 is the only AWD hill mower with spinning LiDAR, which maps the yard in 3D and keeps working when satellites are blocked. That makes it the pick for wooded hillsides, lawns beside two-story houses, and yards with metal roofs nearby. TechRadar called it “highly recommended” for large, complex lawns with steep terrain, and independent lab testing in early 2026 rated it the best wire-free robot on the market for complex ground. It also includes three years of cellular service.
Know before you buy: it comes in a low-cut version (1.0–2.7 in) and a high-cut version (2.2–4.0 in), and you cannot switch later. Southern Bermuda and Zoysia lawns need the low-cut model. Its front casters can also scuff wet, shaded turf on turns. Full head-to-head: LUBA 3 AWD vs Navimow X430.
3. Mammotion LUBA mini 2 AWD: best for a small steep yard
$1,999 | 80% (38.6°) | up to 0.37 acre | AWD | LiDAR + RTK + cameras
Same climbing ability and the same three-way navigation as the LUBA 3, in a smaller package for yards under about a third of an acre. Bob Vila named it best for complex yards. If your lot is small but steep, this saves you $400 to $1,000 over the full-size mowers without giving up traction.
4. Dreame A3 AWD Pro: steepest rating on paper, with a warning
$3,199 | 80% (38.6°) | 0.62 to 1.24 acres | AWD | 3D LiDAR + cameras
Bob Vila picked the A3 as best for steep slopes, and its LiDAR plus dual cameras make it a strong tree-cover option too. But Reviewed’s experience was rough: setup “froze at 72% calibration for two weeks,” it needed to sit beside the router to connect, and once running it “repeatedly overshot mapped boundaries to turn around in the mulch beds, digging up plants.” Two respected testers, two very different experiences. It is the most expensive mower here, so we would wait for the firmware to settle, or buy from a retailer with an easy return window.
5. Lymow One Plus: best for rough ground, roots and leaves
$2,999 | 45° (100%) | 0.5+ acre per charge | tracked | RTK + cameras
The Lymow is the only tracked mower in the group. Tracks spread the weight over a long footprint instead of four contact patches, which is why it can be rated for 45° and why it handles wet cross-slopes, exposed roots and leaf litter that stop wheeled mowers. It is the pick for the “lawn” that is really a hillside field. Reviewed is still testing it, so our recommendation rests on the design and early reports rather than a finished long-term review.
6. Husqvarna Automower 435X AWD: the dealer-installed option
$2,999.99 | 70% (35°) | up to 0.9 acre | AWD | boundary wire
Husqvarna’s AWD mower has been climbing hills since before most of these brands existed, and if you want a local dealer to install it and fix it, that matters. The trade-off is a lower slope rating than the Chinese AWD mowers, a narrow 8.7-inch deck, and, on this model, a buried boundary wire. Husqvarna’s newer NERA wire-free models cost more and are worth asking the dealer about.
Skip these on a hill
Popular mowers that are fine on flat ground and wrong for slopes:
- Eufy E15 / E18: 18° maximum, rear-wheel drive. Great setup, will not climb.
- Segway Navimow i105N / i110N: 16° maximum. Excellent value on flat lawns only.
- Worx Landroid Vision: 17° maximum. Built for big flat lawns, not hills.
- Ecovacs Goat A3000: 27°. Reviewed’s best overall, and a good pick for moderate slopes, but it is outclassed above 25° by the AWD mowers.
Bottom line
Measure your slope first. If it is under 18°, you do not need a hill mower and you can save $1,000. If it is steeper, buy all-wheel drive, add a 5 to 10 degree margin, and choose by what is above the hill: open sky means Navimow X430, trees mean LUBA 3 AWD. And whichever you pick, mow when it is dry and check the turnarounds after week one.
Specs and prices are from the manufacturers and from hands-on reviews by Reviewed, Bob Vila, PCWorld and TechRadar, current as of September 2026. Prices move with sales, so check before you buy.