Smart Locks Compared: Deadbolt, Lever, Retrofit, and Built-In Types in 2026

Smart locks are not a single product category. The label covers four distinct hardware approaches with different installation requirements, connectivity options, and security profiles. A retrofit smart lock that mounts to your existing deadbolt is a fundamentally different product from a built-in lock that replaces the entire mortise assembly. Buying the wrong type for your door, your network, or your rental situation leads to frustration. This guide walks through the four main types, what each is good at, and how to pick the right one for your setup.

The four smart lock types

Smart locks split into four hardware categories. Retrofit locks attach to the interior side of your existing deadbolt and turn the thumbturn for you. Replacement deadbolts swap the entire deadbolt assembly with a smart version that includes a keypad, fingerprint sensor, or both. Smart levers replace a lever-style handleset, common in interior doors and some commercial applications. Built-in or mortise smart locks integrate into European-style multipoint locking systems, often combined with smart handles.

Each type has different installation requirements, exterior appearance, and feature sets. Retrofit locks preserve the original exterior hardware. Replacement deadbolts change the look of the door. Levers fit specific door configurations. Mortise locks require professional installation and are common in high-end residential and commercial applications.

Retrofit smart locks

Retrofit locks like the August Wi-Fi Smart Lock and the Level Bolt sit on the interior of the door and turn the existing thumbturn motor-driven. They install in 15 to 25 minutes with a screwdriver, do not require a locksmith, and preserve the original key and exterior hardware. The August has a visible round body about 3 inches in diameter. The Level Bolt hides inside the deadbolt itself, making it invisible from both sides.

The trade-off is feature limitations. Retrofit locks usually do not include a keypad, since the exterior hardware is unchanged. Entry is by app, Apple Home Key, Auto-Unlock geofencing, or the original physical key. If you want PIN code entry without a phone, a retrofit lock is not the right choice unless you add a separate keypad accessory.

Retrofit is the ideal choice for renters, for households that already love their existing deadbolt, and for anyone who wants to avoid changing the exterior appearance of the door. The installation is reversible, the key still works, and the smart features are bolted on rather than baked in.

Replacement smart deadbolts

Replacement deadbolts like the Schlage Encode Plus, Yale Assure Lock 2, Aqara U200, and Eufy Security E330 replace the entire deadbolt assembly. They include a keypad on the exterior, often paired with a fingerprint reader, NFC, or both. The interior side has a thumbturn or motorized actuator. Most include physical key backup with an industry-standard cylinder (Schlage C, Kwikset KW1, or SC1).

Installation is more involved than retrofit. Expect 25 to 45 minutes with a screwdriver. The door must have a standard 2-1/8 inch bore hole and a standard 1 inch latch bore. Most replacement deadbolts handle door thicknesses from 1-3/8 to 2-1/4 inches. Measure before buying. The Aqara U200 is notable for handling thicker doors (up to 3-1/4 inches) without modifications.

Replacement deadbolts are the mainstream choice for homeowners. They offer the most features per dollar, work standalone with a keypad if the network fails, and integrate with all major ecosystems through Matter, Z-Wave, Zigbee, or Wi-Fi depending on the model.

Smart levers

Smart levers replace lever-style handlesets on interior or exterior doors. Common configurations include ADA-compliant lever handles for accessibility, office doors, garage entry doors, and some side entry doors on modern homes. Schlage, Kwikset, and Yale all make smart lever options.

Levers come in two variants. Storeroom function levers are always locked from the outside and unlock with a key or PIN. Passage levers with deadbolt combo combine a lever handle with a separate smart deadbolt above it. For most residential use cases on a main entry door, a smart deadbolt above a regular passage lever is more secure and more common than a true smart lever.

Smart levers make sense for garage entry doors (where you want quick keypad entry from the garage), for ADA-compliant entry doors, and for interior office doors. They are uncommon on front doors in most regions.

Built-in and mortise smart locks

Built-in smart locks integrate into the door itself, typically in European-style multipoint locking systems. Brands include FUHR, KFV, Winkhaus, and some high-end Yale models. Installation is professional and usually happens when a new door is manufactured or when retrofitting an existing multipoint door.

Multipoint locks engage three or more locking points (top, middle, bottom) when the handle is lifted, providing significantly better security than a single deadbolt. The smart variant motorizes the locking action and adds keypad, fingerprint, or app control on the exterior handle.

This category is the right choice for high-security applications, for premium new construction, and for European-style doors that already have multipoint hardware. The cost is substantially higher (often 600 to 1500 dollars installed) and the lockset is not user-replaceable.

Connectivity and entry methods

Smart locks use several different networking protocols. Wi-Fi locks connect directly to your home router. Wi-Fi simplifies remote access but drains batteries faster, typically 3 to 6 months on 4 AA batteries. Z-Wave and Zigbee locks require a hub but use much less power, typically 6 to 9 months of battery life. Bluetooth-only locks work in-range without any network, with the best battery life of the older protocols at 9 to 12 months. Matter-over-Thread locks released since 2024 combine the power efficiency of Thread with the cross-ecosystem compatibility of Matter, achieving 10 to 14 months. Locks like the Aqara U200, Yale Assure Lock 2 Plus with Matter, and Schlage Encode Plus support Matter directly.

Entry methods include phone unlocking via app or NFC tap, geofencing auto-unlock when you arrive home, PIN code on a keypad, fingerprint biometrics, Apple Home Key NFC, and physical key backup. PIN code is the most reliable method because it works without your phone and without the network. Fingerprint is fastest but fails for some users (wet hands, scarred fingerprints) and adds 30 to 80 dollars to the price. Apple Home Key is convenient for iPhone households but only works on locks that explicitly support it.

For most households, a lock with both a keypad and a physical key backup covers all scenarios. Add fingerprint if multiple household members use the lock daily and want the fastest entry.

What to check before buying

Measure the door thickness (most locks fit 1-3/8 to 2-1/4 inches; some fit thicker). Measure the bore hole diameter (standard is 2-1/8 inches). Identify the backset (typically 2-3/8 or 2-3/4 inches between the door edge and the center of the bore). Confirm whether you want to keep your existing key (Schlage C, Kwikset KW1, SC1) or are willing to rekey.

Check what smart home ecosystem you use. Apple Home households should look for Matter or HomeKit. Google and Amazon households should look for Matter or Wi-Fi-direct. SmartThings households can use Z-Wave, Zigbee, or Matter.

For our take on related decisions see the smart-bulb vs smart-switch comparison and our methodology at /methodology.

Frequently asked questions