What's the weight limit on a stairlift?
There is no single number. Capacity is a published rating on a specific model, for a specific rail. Exceed it and you overburden the motor. Bruno says that plainly.
Most household stairlifts sit between 300 and 400 lb. Stannah writes that most of its lifts support 300 to 350 lb. Bruno sells 300 lb (Elan) and 400 lb (Elite). Savaria's comparison chart runs from 275 lb on the Freecurve up to 440 lb optional on the 1000. Harmar's Pinnacle SL600HD sell sheet calls that model the industry's only 600 lb stairlift.
Need A Stairlift does not sell stairlifts. We collect competing installer quotes for $50. The rider's weight belongs on the request because it changes which models an installer can offer.
Straight vs curved can change the number
On the same brand, a curve is often rated lower than a straight.
Stannah publishes these figures:
- Siena and Starla straight: 350 lb
- Siena and Starla curved: 300 lb
- Same chairs with the 260 Plus heavy-duty option on a curve: 352 lb
- Sadler perch seat: 300 lb
- Outdoor: 300 lb
Bruno's Elite is 400 lb on indoor or outdoor, straight or curved. The Elan is 300 lb and only for indoor straight stairs. That split is on Bruno's basics page.
Savaria's compare chart:
- Straight K2: 300 lb standard, 350 lb optional
- Straight K2+: 400 lb
- Straight 1000: 350 lb standard, 440 lb optional
- Straight 1100: 310 lb
- Curved Stairfriend 23 and Handicare 4000: 300 lb standard, 350 lb optional
- Curved Freecurve: 275 lb
If one quote is a 300 lb curved chair and another is a 400 lb straight, they are not the same job. More on the rail difference in do stairlifts work on curved stairs.
Heavy-duty is more than a bigger sticker
Bruno's 400 lb Elite uses a more powerful motor, larger batteries, and heavier-duty parts than the 300 lb Elan, and it costs more. They also sell a larger seat on Elite indoor lifts: a wider pad and more space between the armrests. A pound rating without a seat that actually fits is not useful.
Harmar's SL600HD is a straight-rail heavy-duty unit. The sell sheet lists 600 lb capacity, a high-backed extra-wide seat, stationary armrests, and a reinforced footrest. That rating is for this model. Do not assume the same number exists on a custom curve. Ask.
Leave some room under the rating. A coat, shoes, and the way someone sits all add weight. The published figure is a maximum, not a target.
What to put on the quote request
Give the rider's current weight honestly. Installers never get your last name, phone, or email from us, but they do get rider facts that affect the fit, including weight. That is how they know whether a 300 lb chair is even on the table.
When the quotes come back, line them up on:
- Published capacity for that exact model
- Straight or curved, matching your stairs
- Seat width, not just the pound rating
- Price, warranty, and who services it
A national brand can still quote $7,000 or more for a straight lift that a local installer prices for much less. Capacity is one column, not the whole email. Brand differences beyond weight are in best stairlift brands.