The only residential stair lift on the market rated for 600 pounds. Same patented grease-free worm drive as our flagship — engineered with an extra-wide chair and reinforced structure for heavier users, and backed by a true lifetime warranty.
The Nautilus Heavy Duty is the industry's only stair lift rated for 600 pounds — nearly double the capacity of most residential stair lifts on the market. That capacity doesn't come from beefing up a lighter chair; it's the result of engineering choices made throughout the lift.
Rated higher than every other residential stair lift in production.
Not a heavier version of a different mechanism — the same reliable drive as our flagship, engineered here for higher loads.
Padded contoured seat with reinforced footrest and stationary armrests for maximum stability.
Pivots 85° while sliding out from the wall at both landings — installs closer to the wall and makes dismounting easier.
| Weight capacity | 600 lbs (272 kg) — industry-leading |
|---|---|
| Drive system | Patented helical worm gear with reinforced nylon polymer gear rack |
| Seat dimensions | 18.5" W × 14" D |
| Backrest dimensions | 17.6" W × 17" H (extra-tall, high-backed) |
| Armrests | Stationary padded, for stability during transfers |
| Footrest | Reinforced, manual flip-up (power fold optional) |
| Folded width | 17" |
| Track length | 15'6" standard; expandable up to 40' |
| Travel speed | 14 feet per minute |
| Incline range | 27° to 48° (above 45° may require local jurisdiction approval) |
| Power | 120–240 VAC standard outlet; 24V DC battery (two 12V 7Ah sealed lead-acid) |
| Battery backup | Up to 60 round trips during a power outage |
| Charging | Charge contacts at upper & lower landings |
| Swivel seat | Slide-swivel — 85° pivot with slide-out motion at upper landing (power swivel optional) |
| Seat belt | Standard retractable, extended length for the HD chair |
| Controls | Armrest toggle with LED indicators plus wireless remote controls |
| Safety systems | Footrest and chassis obstruction sensors, 85° swivel interlock, centrifugal overspeed brake, motor brake, lockable battery/breaker switch |
| Certification | ETL certified to ASME A18.1 |
| Manufactured in | United States (Sarasota, FL) |
The lift itself — chair, carriage, motor, drive system
Custom-cut rail (15'6" standard length)
Two wireless remote controls
Extended-length retractable seat belt
Battery backup system, pre-installed
Professional installation by factory-trained technician
On-site operation training
Lifetime warranty activation
to clear doorways or walkways at the bottom of stairs
disables operation when removed
motorized slide-swivel at top landing
motorized fold/unfold
beyond the 15'6" standard, up to 40' maximum
for manual descent in emergencies
Add-ons are quoted during your free in-home assessment.
We measure your staircase and give you a real quote on the spot.
30 minYour custom-length rail is manufactured at the factory.
2–3 daysFactory-trained technician installs and calibrates the lift.
4–6 hrsOperation and safety training for you and your household.
Same dayYour 24/7 line and warranty are active from day one.
Day oneA quick look at how our four lifts compare.
| Lift | Staircase | Capacity | Drive system | Special feature | Made in | Best for |
|---|---|---|---|---|---|---|
| Nautilus Premium Stair Lift | Straight | 350 lbs | Grease-free worm | Narrowest fold (10.5") | USA | Standard straight stairs |
| Nautilus Heavy Duty Stair Lift | Straight | 600 lbs | Grease-free worm | 600 lb capacity | USA | Heavier users, straight stairs |
| Flow X Curved Stair Lift | Curved | 275 lbs | Rack & pinion | ASL auto-swivel | International | Narrow, spiral, or steep curved staircases |
| Harmar CSL500 Helix Curved | Curved | 350 lbs | Rack & pinion | True-Curve rail | USA (Sarasota, FL) | Curved staircases, US-made preference |
Choose the Heavy Duty if the primary user weighs more than 350 lb, if you want a wider seat and more back support for daily long-term use, or if you’re considering the lift for multiple users of different sizes. The Heavy Duty also has stationary armrests (vs the Premium’s flip-up), which provide more stability during transfers for users with limited mobility.
The Heavy Duty runs at 14 feet per minute vs the Premium’s 20 FPM. This is a deliberate engineering trade-off — the slower speed allows the motor to safely handle up to 600 lb of load. You’re trading a few seconds per trip for the industry’s highest weight capacity.
The Heavy Duty’s seat pivots 85° while simultaneously sliding out from the wall at the landings. This does two things: it allows the lift to install closer to the wall (freeing up staircase width), and it makes dismounting easier because the seat comes toward you rather than requiring you to step forward. The Premium doesn’t have this feature.
The lift runs on battery power at all times, with the standard outlet just providing the charge. A fully charged battery gives you up to 60 round trips — enough for days of normal use during even extended outages.
Traditional Medicare (Part A/B) does not cover stair lifts. Some Medicare Advantage plans, long-term care insurance policies, VA benefits, and state Medicaid waivers may contribute toward the cost. We can walk through your options during your free assessment.
Our lifetime warranty is tied to the original purchaser at the original installation address, which is the industry standard. If you’re moving, we can reinstall your lift at your new home using an authorized Nautilus technician. Any modifications required for the new staircase are quoted separately.
Typically under a week. Assessment takes about 30 minutes on-site, your custom rail is cut in 2–3 business days at the factory, and installation is a 4–6 hour appointment.
In their own words
Two customers on what changed the day their lift went in.
"It's very easy to use."
— Nautilus customer
"It's great. [Installation] was very quick!"
— Nautilus customer
A 30-minute visit gets you a measured stairway, a fixed price, and no obligation.
Call (801) 421-3299Restoring freedom, one stair at a time.