A saddle chair, also known as a saddle stool or saddle seat, is a type of ergonomic seating designed to promote better posture and reduce strain on the back, neck, and shoulders. It is called a "saddle chair" because its shape resembles that of a horse saddle. Saddle chairs typically consist of a saddle-shaped seat with no backrest, and they are often mounted on a height-adjustable central column or post, allowing users to customize the seat height to suit their needs.

The unique design of a saddle chair encourages the user to sit in a position that resembles riding a horse, with the legs separated and hanging down on each side of the saddle. This posture opens up the hip angle and maintains a more natural S-shaped curve in the spine, reducing pressure on the lumbar region and promoting better spinal alignment. By eliminating the backrest, saddle chairs also encourage users to engage their core muscles, which can strengthen the lower back and improve overall posture.

Saddle chairs are commonly used in various professional settings where maintaining an upright and ergonomic posture is essential. These settings include dental and medical offices, hair salons, and some office workstations. Saddle chairs can help reduce the risk of developing musculoskeletal problems associated with poor posture and prolonged sitting. However, they may take some time to get used to, and users may need to gradually adjust to the new sitting position.