A deadlatch will self-latch when the door is closed, unlike a deadbolt which must first be extended. It also cannot be opened by end pressure against the latch when the door is closed, but may be retracted by either the knob/lever or key.

The 127mm backset of the deadlatch is ideal in situations where the stile may cause difficulty in using a knobset with the standard 60 mm - 70 mm backset.