A mortice lock is a locking mechanism requiring a pocket—the mortice—to be cut into the door or piece of furniture into which the lock is to be fitted. Characterised by its embedding within the door, it contrasts with surface-mounted locks and offers enhanced security due to its internal complexity and the difficulty of forced entry. This type of lock typically comprises two main components: the lock body, which is installed inside the mortice cut in the door, and the lock trim, which may be a knob, lever, or handle set visible on the exterior of the door.
Common in both residential and commercial settings, mortice locks require precise installation by skilled carpenters or locksmiths due to the need for exact cutting into the door material. They are available in various configurations, including sash locks, which incorporate a latch and a deadlock, and deadlocks, which only offer a locking bolt moved by a key. Mortice locks are favored for their reliability, durability, and customization options, allowing for different levels of security and aesthetic compatibility with door designs. The choice of a mortice lock often reflects a commitment to both security and architectural integrity.