Steps on vicinal Si(001) are either one or two atomic layers high. When the tilt of the surface about [11̄0] is 2°, alternating type‐A and type‐B single steps dominate. When the tilt angle is increased to 4°, the steps combine to form straight, evenly spaced type‐B double steps. Type‐A double steps do not occur. At kinks the double steps split into single steps. Tunneling images of the double steps reveal the rebonded atoms described by the Chadi model.