Smart locks & keyless entry

Old mortise lock on your front door? Your real options

Plenty of older homes in North Jersey still have their original front door with a mortise lock in it. They are beautifully made, and nothing you buy off the shelf fits them.

By Timmy Creighton, founder and licensed locksmith · Major Key Locksmith · October 2026

How to tell if you have one

A mortise lock is a rectangular box set into a deep pocket cut in the edge of the door. From the outside you usually see a handle or knob with a thumb latch, and a key cylinder set above or below it, often on a long decorative plate. On the edge of the door you will see a tall faceplate with both a latch and a bolt in it. If your lock is a simple round deadbolt in a round hole, it is not a mortise lock.

Option 1 · Keep it and keep it working

A good mortise lock can last generations. When they misbehave it is usually a sticking latch, a worn cylinder, or a door that has dropped so the bolt rubs. Many of those are repairs. The cylinder can usually be rekeyed to match the rest of your house.

Option 2 · Replace the lock body

If the mechanism is worn out, a new mortise body can often be fitted into the existing pocket. Sizes vary a lot on older doors, so this is measured on site.

Option 3 · Convert it to take a smart lock

This is what most people are really asking for. A conversion fills and plates the old mortise pocket and prepares the door for modern hardware, so a smart deadbolt and a matching handleset sit properly on a door they were never designed for. Done well, it looks deliberate rather than patched.

If you supply the lock, the conversion is from $1,150 all-in. We also do the whole thing with our own smart lock and a decorative handleset. The full breakdown is on the mortise conversion page.

Please do not pull it out first

The most expensive version of this job is the one where someone has already removed the old lock and left a large hole in the door edge. It can usually still be saved, but it is more work than converting a door that still has its lock in it.

Questions people ask

Can you put a regular smart deadbolt on a mortise door?

Not directly. The door was never bored for one. It needs a conversion so the new lock has something solid to sit in.

Can a mortise lock be rekeyed?

Usually, yes. Mortise cylinders unscrew from the lock body and can be rekeyed like any other cylinder.

Is a mortise lock less secure than a modern deadbolt?

Not necessarily. A quality mortise lock with a solid bolt is strong. Many old ones have very simple cylinders, though, and those are easy to improve.

Keep reading

Any price mentioned here is the one published on our pricing page as of October 2026. The final price is always confirmed with you before any work begins. More answers from the blog →