How to Install a Deadbolt Lock on a Door | Door Prep to Final Test

Whether you are replacing an old lock or adding a fresh layer of security to a new door, the process for installing a deadbolt lock on a door comes down to a clear sequence: check the door’s prep, fit the bolt, mount the two housings, align the strike plate, and test everything before you close the door for good. Schlage’s own installation manuals spell out the steps, and we have condensed them here into a guide you can follow in one sitting. The single most important rule: test the lock with the door open so you never get locked out mid-project.

Check Your Door Prep and Backset First

Before any hardware goes in, confirm the door is ready for a deadbolt. Standard US residential doors use a 2 1/8-inch crossbore (the big hole for the lock body) and an edge bore for the bolt. The backset — the distance from the door edge to the center of the crossbore — is usually 2 3/8 inches or 2 3/4 inches.

Schlage’s instructions say to verify this prep before starting. For the B60/B62 series, that means checking the door and, on certain models like the B60F with a UL listing, installing the included UL cup. The crossbore and edge bore sizes are standard on prepped doors, but measure to be sure — a mismatch means the lock will not sit flush.

The backset determines whether you need to adjust the bolt. Schlage says a 2 3/8-inch backset requires no adjustment. For a 2 3/4-inch backset, you twist the faceplate to extend the bolt to the longer setting. This takes ten seconds now and saves you from a lock that binds later.

Install the Bolt and Mount the Exterior Housing

The bolt assembly goes in first. Schlage’s triple-option deadbolt guide says to orient the bolt with the word “top” facing up. Most models let you choose between a rectangular faceplate secured with two short screws, or a round drive-in faceplate that you tap flush using a block of wood and a hammer — the block protects the door edge from dents. Not every model supports both, so check the box for the hardware you have.

With the bolt in place, mount the exterior housing. Schlage says to install the outside assembly with the logo facing up, then align the tailpiece with the bolt’s slot. From the inside, secure the thumbturn with the two long screws. If you are installing a smart deadbolt like the BE375, this step includes more than screws — you will route the wiring through the bolt’s slot, connect the harness, and load batteries before securing the interior assembly. Schlage’s warning applies to every deadbolt but matters most on these: the bolt must remain retracted throughout installation, and you should install and test the lock with the door open to avoid being locked out.

Align and Secure the Strike Plate

With the lock body mounted, close the door and mark where the bolt lands on the frame. The strike plate must sit so the bolt slides fully into the hole without dragging on the edges.

Schlage notes that a reinforcement plate on the door frame is optional. If you use one, secure the strike plate over it; otherwise, attach the strike plate directly to the frame using the remaining short screws. Schlage’s installation manual specifies that the strike hole itself must be at least 1 1/4 inches (32 mm) deep so the bolt has full clearance. On the BE375, the strike hole depth is a listed requirement, not a suggestion — a shallow hole stops the bolt from seating fully.

If the bolt drags or hits the strike plate instead of sliding through, adjust the strike plate’s position or file the doorjamb slightly. Improper strike alignment is the most common cause of a deadbolt that binds, and Schlage’s guides say the fix is adjusting the strike or jamb until the bolt extends and retracts smoothly.

Test the Lock Before You Close the Door

Testing is not the last step — it is the step that keeps you from calling a locksmith. With the door open, use the thumbturn and the key to cycle the bolt several times. It should extend and retract with smooth, even resistance.

Only after that passes, close the door and test again. The bolt should slide into the strike plate without scraping. If it does not, revisit the strike plate alignment. When the bolt moves cleanly both ways, the installation is done. You now have a functioning deadbolt on a properly prepped door.

If you are shopping for a new deadbolt rather than installing one you already own, our roundup of the best door locks and deadbolts on the market compares the top picks by security rating, ease of install, and smart features, so you can choose the right one before you pick up a screwdriver.