A shoulder strap is a strap over a shoulder. They are often affixed to women's dresses to support its weight or as part of its style. The term is also applied to carrying bags and to epaulettes.

A carrier shoulder strap is a length of fabric or other flexible material (such as leather, vinyl, rubber), used to suspend an item, often of some weight, from the shoulder(s). The strap may be worn slung over one shoulder or across the body. In the interest of comfort, they often have some manner of padding near the middle, where the strap rests directly against the shoulder or neck. Such items include purses, guitars, rifles, etc. In the case of rifles and other such weaponry, the shoulder strap is usually referred to as a sling. Shoulder straps may also be used in pairs on such items as a backpack or a baby carrier; the straps are worn one over each shoulder, and the item so carried is centred on the back or chest.

The use of such straps frees the hands for other use.

Also use to store gloves

A shirt shoulder strap or passant is a length of fabric on a shirt, blouse, or jacket that runs along the length of the shoulder. It is usually stitched into the shoulder seam and fastened with a button, snap fastener, or hook-and-loop fastener near the collar. They are usually found on military or civilian uniforms and are used to attach epaulettes, brassards, lanyards, shoulder marks or other insignia to the uniform. These straps were originally devised and used to hold the cross belt (and back pouch) in place; to stop it from riding up on to the wearers neck. Shoulder straps are also found on uniform-derived clothing such as a trench coat or a safari jacket. Civilian uniforms that may use shoulder straps include park rangers, police officers, Scouts and Guides.