A basic standard manual wheelchair incorporates a seat and back, two small front (caster) wheels and two large wheels, one on each side, and a foot rest.

Most wheelchairs are variations on this basic design, but there are many types of wheelchairs, and they are often highly customized for the individual user's needs. The seat size (width and depth), seat-to-floor height, footrests/leg rests, front caster outriggers, adjustable backrests, controls, and many other features can be customized on, or added to, many basic models, while some users, often those with specialized needs, may have wheelchairs custom-built.

Various optional accessories are available, such as anti-tip bars or wheels, safety belts, adjustable backrests, tilt and/or recline features, extra support for limbs or neck, mounts or carrying devices for crutches, walkers or oxygen tanks, drink holders, and clothing protectors.

Experiments have also been made with unusual variant wheels, like the omniwheel or the mecanum wheel. These allow more directional movement options. The electric wheelchair shown on the right is fitted with Mecanum wheels (sometimes known as Ilon wheels) which give it complete freedom of movement. It can be driven forwards, backwards, sideways, and diagonally, and also turned round on the spot or turned around while moving, all operated from a simple joystick.

Manual wheelchairs

• Ricon Corporation - specializes in the design, manufacture and sale of wheelchair lifts for vans, buses, recreational vehicles and passenger rail cars.
• Vantage Mini Vans - manufacturer of minivan conversions for people with disabilities.
• Independent Mobility Systems, Inc. - manufactures the wheelchair friendly, lowered floor Rampvan.
• Ride-Away Handicap Equipment Corp. - manufacturer and dealer of vehicles and equipment for people with disabilities.
• Liberty Motor Co. Inc. - specializes in sales of pre-owned, modified, wheelchair accessible minivans.
• Automobility - program that enables people with disabilities to outfit their Dodge, Chrysler, and Jeep vehicles with adaptive equipment.
• Access Mobility Systems - offers mobility equipment tailored to your needs.
• Creative Mobility - [SPONSOR] - specialists in handicapped-mobility van conversions.
• Freedom Motors - designs and manufactures the KneelKar van conversion for the physically challenged, for personal and commercial use.
• Nor-Cal Mobility - van conversions and adaptive driving equipment for people with disabilities.