How to Install a Smart Lock

Short version: installing a smart lock is a same-afternoon DIY job for the vast majority of homeowners, requiring nothing more than a Phillips screwdriver, because nearly every smart lock is designed to retrofit the same standard deadbolt hole pattern already cut into your door.

In Plain English

Tools You'll Need (Screwdriver and Template)

A Phillips screwdriver handles the vast majority of smart lock installs on its own, since these locks are built as a direct retrofit for an existing deadbolt hole rather than requiring any new drilling. Some kits include a small hex key or the few additional fasteners needed for their specific mounting plate — check the box contents before you start so you're not hunting for a tool mid-install. A tape measure is worth having on hand too, for confirming your door's backset and thickness before you even open the box.

Step 1: Check Door Compatibility

Measure your door’s backset (the distance from the door’s edge to the center of the deadbolt hole — commonly 2-3/8" or 2-3/4") and door thickness (typically 1-3/8" to 1-3/4"). Check these against the specific smart lock’s listed compatibility range before ordering. This single check prevents the most common reason for a return in this category. If your door uses a less common backset or an unusually thick slab, confirm compatibility with the specific listing rather than assuming a universal fit.

Step 2: Remove the Existing Deadbolt

Unscrew and remove the interior and exterior halves of the existing deadbolt, along with the strike plate on the door frame if you’re replacing it too. Keep the screws in case you need them as a reference for length. With both halves off, the bolt mechanism itself should slide straight out of the edge of the door — if it's stuck, a light tap with a screwdriver handle usually frees it without any damage to the door.

Step 3: Install the New Deadbolt and Check Bolt Alignment

Insert the new deadbolt mechanism into the existing hole, following the manufacturer’s included instructions for orientation — most kits include a paper template to confirm placement before you commit. Fit the exterior keypad or fingerprint assembly (the same step as when you install a keyless entry door lock), then attach the interior assembly (which houses the battery compartment) and secure with the included screws, snug but not over-tightened, since forcing the screws can bind the bolt's movement. Close the door slowly and check that the bolt lines up cleanly with the strike plate hole before you fully commit to the position; a small mismatch here is normal and usually solved by adjusting the latch or repositioning the strike plate.

What Consumer Reports says. While you have the old hardware out, it is worth reading Consumer Reports' door lock buying guide. It notes that smart locks are "just as susceptible to forced entry as nonconnected locks," and recommends upgrading the strike plate to one fastened with 3-inch screws driven into the house framing, a cheap fix that strengthens the door whatever lock you fit.

Step 4: Insert Batteries and Run Calibration

Insert batteries, then let the lock run its initial calibration cycle if the manufacturer's instructions call for one — most WiFi and app-connected locks extend and retract the bolt once on first power-up to learn its own travel distance. Skipping this step is a common cause of a lock that later reports the wrong locked or unlocked status in the app, so follow the included instructions exactly rather than assuming it isn't necessary.

Step 5: Set Up Codes and Pair the App

Follow the manufacturer’s app pairing process if the lock is WiFi or Bluetooth-connected — this typically involves scanning a QR code or entering a setup code shown on the lock itself, then connecting to your home WiFi network. Set your primary entry code and any additional household codes before finishing, and rename the lock in the app to something you'll recognize later if you're managing more than one door.

Step 6: Test Before You Rely On It

Test the lock and unlock cycle several times with the door open before closing it, confirm auto-lock behavior (if enabled) with the door closed, and verify a backup entry method (physical key or a second code) actually works. Testing thoroughly in the first few days catches an install issue while you still have the return window open, and it's far easier to fix a sticking bolt now than after you've relied on it for weeks.

Troubleshooting Common Install Issues

A bolt that won't fully extend or retract usually points to a door alignment issue rather than a defective lock — loosen and re-shim the strike plate, and check that the door itself closes flush without needing to be pulled or slammed. A lock that won't pair with the app is most often a WiFi signal issue at the door rather than a broken lock; confirm you're joining a 2.4GHz network (Schlage, for example, requires 2.4GHz WiFi for the Encode), move your router closer, add a mesh extender, or check the manufacturer's app for a signal-strength reading during setup. If the keypad or fingerprint sensor is unresponsive, reseat the batteries first — a poor battery contact is a far more common culprit than a failed sensor.

When to Call a Locksmith Instead

Non-standard door prep, a damaged or misaligned existing deadbolt, or a door that’s out of square enough that the deadbolt binds are all reasons to bring in a locksmith rather than force an install. If your door is failing to latch cleanly with the old deadbolt already, fix that first — a smart lock’s auto-lock feature depends on the door closing and latching properly. A locksmith is also the safer call if you're dealing with a commercial-grade door, a fire-rated door assembly, or any situation where drilling a new hole (rather than a simple retrofit) is required.

Ongoing Maintenance After Install

Replace batteries proactively once the app or keypad starts giving low-battery warnings, rather than waiting for a full drain — most smart locks give a genuine grace period once the warning appears, but there's no reason to test how long it actually lasts. Wipe down the exterior keypad or touchscreen occasionally, since dust and finger oils can affect touch-sensitive keypads over time more than they affect a purely mechanical one. If you notice the bolt starting to drag or feel gritty as it extends, a small amount of the lubricant the manufacturer recommends — typically a dry lubricant rather than a general-purpose oil, which can attract dust — usually resolves it. Re-check the mounting screws for tightness after the first few weeks of regular use, since normal door movement can work them slightly loose.

Going Deeper: Why Backset and Door Thickness Decide the Fit

Residential deadbolts are built around a small set of standard door-prep dimensions, and that is what makes a screwdriver-only retrofit possible. Kwikset’s door-prep specification for its 660 deadbolt calls for a 2-1/8" bore hole, a backset of 2-3/8" to 2-3/4" and a door 1-3/8" to 1-3/4" thick. Schlage lists the same door-thickness range for the Encode, with a universal backset that adjusts to either 2-3/8" (60 mm) or 2-3/4" (70 mm). When two major brands design around identical numbers, a door drilled for one usually accepts the other.

The backset matters because the new bolt, which sits in the edge of the door, has to line up with the centre of the bore hole where the inside and outside halves of the lock meet. An adjustable latch simply switches between the two standard settings. If your measurement falls outside both, careful fitting will not make the parts line up, and that is the point where a locksmith, not a different screwdriver, is the answer. Thickness works the same way. Kwikset notes that its deadbolts fit 1-3/8" to 1-3/4" doors as standard, and that a separate thick-door kit is available for doors up to 2-1/4".

The same manufacturer specifications explain two other steps in this guide. Schlage states that the Encode requires a 2.4GHz WiFi network, so when app pairing fails, the router band is worth checking before the lock itself. It also rates the Encode at up to six months on four AA alkaline batteries with typical use, which is why replacing batteries promptly after the first low-battery warning, rather than testing how long the grace period lasts, is part of routine maintenance.

Ready to Buy?

See best smart lock for ranked picks across every entry method and connectivity type, or the smart locks buying guide for choosing between keypad, fingerprint and app entry.

Related: see also Smart Garage FAQs, Smart Lock vs Traditional Deadbolt and Schlage Encode vs Yale Assure.