When am I allowed to lift off the court while defending?

Lifting is permitted all over the court when you play the ball in a defensive action (first, second or third contact), as long as the contact is made when the ball is not entirely higher than the top of the net.

• Your buttocks are also allowed a short loss of contact with the floor at any time and in any area of the court, except when performing an attacking action.
• A loss of contact is allowed as a reaction after performing the action.
• If, after the defensive action, the ball legally crosses the vertical plane of the net, play continues.

Volleyball Canada's sitting volleyball page describes this exception in terms of defensive actions in the back zone; the World ParaVolley 2025-2028 rule text says "all over the court".

Source: World ParaVolley Official Sitting Volleyball Rules 2025-2028, Rule 9.4.1; Volleyball Canada sitting volleyball page.