Smart locks & keyless entry

Will a smart lock fit my door? Measure these five things first

Most smart lock returns are not about the lock. They are about the door. Five quick checks tell you whether a lock will fit, or whether your door needs work first.

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

1 · The bore hole

A modern deadbolt sits in a round hole through the door face, usually 2-1/8 inches across. If your door has that, most smart deadbolts will go straight in. If your lock is a long rectangular body set inside the edge of the door with a handle and a key above or below it, you have a mortise lock, and an ordinary smart deadbolt will not fit without conversion work.

2 · The backset

Backset is the distance from the edge of the door to the center of the bore hole. In the US it is almost always 2-3/8 or 2-3/4 inches. Most deadbolts adjust to both, but check.

3 · Door thickness

Most residential smart deadbolts are made for doors roughly 1-3/8 to 1-3/4 inches thick. Thicker custom doors often need a longer kit from the manufacturer. Measure before you order.

4 · The storm door

The outside keypad sticks out further than a regular deadbolt. If there is a storm door, close it and measure the gap between the two doors where the lock will sit. A keypad that hits the storm door handle is a surprisingly common return.

5 · How the door closes

This is the one that matters most and gets checked least. A smart deadbolt throws its bolt with a small motor. If you have to push or lift the door for a regular deadbolt to lock, the motor will struggle, stall and drain batteries. Fix the strike alignment first, and the lock will work properly for years.

The doors that need more than a lock

• Mortise doors in older homes need a conversion. We do this regularly; it is its own service.
• Multipoint doors, the kind where you lift the handle to lock, need a lock made for multipoint hardware.
• Metal and glass doors on businesses need commercial electronic hardware rather than a residential smart lock.

Already bought one? We will fit it. Installing a customer-supplied electronic lock is $400 on its own visit with the door prep included, and we will tell you on the phone if your door needs anything else first.

Questions people ask

Can a smart lock go on a door that only has a knob?

Yes, but a new bore hole has to be drilled for the deadbolt. Door and frame prep for a new bore is $100 per lock, on top of the $250 mobile service charge, which is charged once per visit.

My door is metal. Can it take a smart lock?

Most residential steel doors come pre-bored and take a smart deadbolt the same way a wooden door does. Commercial hollow-metal doors are usually better served by commercial electronic hardware.

Will installing a smart lock damage my door?

Not on a standard bored door. The new lock uses the same holes. Conversions and new bores do involve cutting, which is why they are priced separately.

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 →