Pro Locksmith NYC Service Team
Local locksmith team
Jun 10, 2026 3 min read
If you've ever stared at the door of a pre-war co-op on the Upper West Side or a brownstone in Park Slope and wondered why the lock looks nothing like the deadbolt on your friend's suburban house, you're not alone. New York City's housing stock spans more than a century of construction styles, and the locks that secure those doors are just as varied. Two types come up again and again for homeowners and building managers: the mortise lock and the cylinder deadbolt. Choosing between them isn't just a matter of preference — it affects security, code compliance, and whether a replacement will even fit your door.
This guide breaks down exactly how each lock type works, where each one shines, and what you should think about before making a change. Whether you're rekeying after a move, upgrading after a break-in scare, or simply replacing worn hardware on a Flatbush two-family, the right information saves you time, money, and a callback to your super.
Frequently asked questions
What is a mortise lock and how is it different from a regular deadbolt?+
A mortise lock is a complete locking mechanism housed inside a rectangular cavity (the mortise) cut into the edge of the door. It typically combines a latch, a deadbolt, and additional lock functions in one unit. A regular cylinder deadbolt installs through two round bored holes and sits on the face of the door rather than inside it. Mortise locks are more common in older NYC buildings because they were the construction standard for most of the twentieth century and offer a high degree of structural integration with the door.
Can I add a smart lock to a door that already has a mortise lock?+
Yes, but you need a product specifically designed as a smart mortise lock — one that replaces the cylinder and trim while leaving the existing lock case inside the door intact. These products are available from several hardware manufacturers and allow keypad, Bluetooth, or app-based access without modifying the door structure. Our team can assess your existing mortise lock set, recommend a compatible smart option, and handle the full installation so the new hardware works correctly with your door geometry and building requirements.
How much does it cost to replace a mortise lock in NYC?+
The price depends on several factors: the brand and model of the replacement mortise lock set (a standard residential unit differs significantly from a high-security Baldwin mortise lock or a Corbin Russwin commercial grade product), whether you're supplying the hardware or we are, the time of day the work is being done, and travel logistics across the borough. We confirm an exact, all-in price before any work begins, so you always know what you're agreeing to before we pick up a tool.
My building says I need to keep the original mortise lock — can you rekey it instead of replacing it?+
Absolutely. Rekeying a mortise lock cylinder is one of the most common requests we handle, especially after a move or a change in tenancy. We remove the existing cylinder, repin it to a new key combination, and reinstall it — the lock case and trim stay exactly as they were, which keeps your building management happy and your door secure with keys that only you control. This is a faster and less invasive service than a full lock replacement and is a smart first step whenever you move into a new apartment in New York City.
