How deep does a cut have to be to get stitches?

Length more impt: Stitches are required when the edges of the wound or cut, cannot easily - naturally - come together or are on a stress area which will cause a cut to continuously re-open. The depth is less important - for instance many stab wounds do not requires suturing but just a piece of tape across the opening.

Sutures: May need stitches if wound depth > 1/4”, wound edges are gaping or jagged or if fat / muscle is visibly extending from wound. If you can’t stop bleeding that requires medical intervention.See: http://www.mayoclinic.org/first-aid/first-aid-cuts/basics/art-20056711