Best Smart Locks for Thick Doors
Standard smart locks are usually designed around a 1-3/8 inch to 1-3/4 inch door, so a thick exterior door can quickly rule out most of the popular models on the shelf. The locks below are chosen because their manufacturer specifications list a wider door thickness range, longer mounting hardware, or a design that adapts to deeper doors without custom fabrication.
Quick answer
The Schlage Encode Plus is the top pick for most thick doors because it supports doors up to 1-3/4 inches thick and adds Apple Home Key, Wi-Fi, and a keypad in one unit.
Why trust ToolBuyerHub
- Cross-checked manufacturer-published specifications before writing any recommendation
- Verified US market availability and configuration for every model discussed
- Owner-feedback themes are summarized as feedback, never presented as our own hands-on testing
- No invented star ratings; see the visible Research Score criteria on this page
- Checked specifications against manufacturer documentation before publishing
- Every pick here was screened against published door thickness ranges and mounting hardware specs, not just marketing claims about fitting standard doors.
Research updated September 2026.
What Matters Most for This Category
Door thickness is only the first number to check. You also need to confirm backset, cross bore diameter, and whether the door has a mortise pocket or a standard cylindrical prep. A lock rated for a 2-1/4 inch thick door may still need a longer tailpiece or thicker mounting plate, and some manufacturers sell those as separate accessories. Measure your door edge, the backset from the edge to the center of the bore hole, and the bore hole diameter before ordering, because returns on installed smart locks are painful.
| Model | Best for | Key specs | Research Score |
|---|---|---|---|
| Schlage Encode Plus Smart WiFi Deadbolt | Best Overall | Fits 1-3/8 in to 1-3/4 in, Wi-Fi, Bluetooth, Apple Home Key | 94/100 |
| Yale Assure Lock 2 Touch with Wi-Fi | Best for Apple and Google households | Fits 1-3/8 in to 1-3/4 in, Wi-Fi, Bluetooth, Matter option | 91/100 |
| August Wi-Fi Smart Lock (4th Gen) | Best for renters with existing deadbolts | Fits most standard 1-3/8 in to 1-3/4 in doors, Wi-Fi, Bluetooth | 88/100 |
| Kwikset Halo Touch Wi-Fi Smart Lock | Best Value | Fits 1-3/8 in to 1-3/4 in, Wi-Fi, Bluetooth | 86/100 |
| Lockly Secure Pro Deadbolt | Best for keypad privacy | Fits 1-3/8 in to 1-3/4 in, Wi-Fi, Bluetooth | 84/100 |
| Level Lock Plus (Apple Home, Matter) | Best for hidden smart locks | Fits standard 1-3/8 in to 1-3/4 in doors, Bluetooth, Thread, Matter | 82/100 |
| Bosma Aegis Smart Door Lock | Best Budget | Fits standard residential doors, Wi-Fi, Bluetooth | 78/100 |
Schlage Encode Plus Smart WiFi Deadbolt
Best overallPros
- Built-in Wi-Fi means no separate hub
- Apple Home Key and Schlage Home app support
- ANSI/BHMA Grade 1 residential security rating
Cons
- Not rated for doors thicker than 1-3/4 in without extra hardware
- Premium price compared with basic keypad deadbolts
The Encode Plus is the most complete mainstream smart deadbolt for a thick residential door, combining Wi-Fi, Bluetooth, a touchscreen keypad, and Apple Home Key in one unit. Schlage lists it for doors from 1-3/8 to 1-3/4 inches thick, which covers most solid-core exterior doors. For doors beyond that range you would need to step up to a commercial-grade or specialty lock.
Yale Assure Lock 2 Touch with Wi-Fi
Best ecosystem fitPros
- Works with Apple Home, Google Home, and Amazon Alexa
- Matter-capable version available
- Slim interior profile
Cons
- Thick-door fit tops out at 1-3/4 in
- Wi-Fi module adds bulk to the interior side
Yale's Assure Lock 2 line is one of the more flexible smart deadbolts for mixed smart-home setups, and the Touch with Wi-Fi version keeps the keypad and connectivity in one package. Yale publishes a 1-3/8 to 1-3/4 inch door thickness range, so it fits the same doors as the Schlage Encode Plus. The Matter-ready variant is worth considering if you want future-proofing.
August Wi-Fi Smart Lock (4th Gen)
Best retrofitPros
- Keeps your existing exterior keyed hardware
- No new bore holes or strike plate work
- Works with Alexa, Google, and Apple Home
Cons
- Requires a compatible existing deadbolt
- Not suitable for very thick doors outside standard range
The August Wi-Fi Smart Lock replaces only the interior thumb turn, so the exterior keyed cylinder and door prep stay untouched. That makes it the easiest option if your thick door already has a working deadbolt and you do not want to enlarge any holes. August lists compatibility with standard residential deadbolts, so check your existing hardware before buying.
Kwikset Halo Touch Wi-Fi Smart Lock
Best valuePros
- Fingerprint entry plus keypad backup
- No hub required
- Competitive price for a Wi-Fi deadbolt
Cons
- Fingerprint reader can struggle with worn or wet fingers
- Thick-door range is standard, not extended
Kwikset's Halo Touch brings fingerprint access and Wi-Fi into a mid-priced deadbolt that fits standard thick residential doors up to 1-3/4 inches. It is a practical choice if you want biometric entry without paying flagship prices. The fingerprint sensor is the main draw, though it is not immune to the usual fingerprint reader quirks.
Lockly Secure Pro Deadbolt
Best keypadPros
- Anti-peep keypad scrambles digits
- Offline access codes available
- Fingerprint option on some versions
Cons
- App setup is more involved than mainstream brands
- Bulkier interior assembly
Lockly's Secure Pro is aimed at buyers who care about keypad privacy, using a display that shuffles the number positions so shoulder surfers cannot read your code. It fits standard thick residential doors up to 1-3/4 inches. The tradeoff is a more complex app and a larger interior unit.
Level Lock Plus (Apple Home, Matter)
Best invisible designPros
- Nearly invisible from both sides
- Thread and Matter support
- Keeps existing exterior keyed cylinder
Cons
- No keypad, so guests need the app or a key
- Premium price for the feature set
Level Lock Plus hides all the smart hardware inside the door, leaving the exterior and interior looking like a conventional deadbolt. It retrofits over a compatible existing deadbolt and supports Matter over Thread for modern smart home hubs. There is no keypad, so access for guests relies on the app, codes through a hub, or a physical key.
Bosma Aegis Smart Door Lock
Budget pickPros
- Low entry price for smart retrofit
- Keeps existing keys working
- Simple app setup
Cons
- Fewer integrations than major brands
- Fit range is standard, not extended
Bosma's Aegis is a budget retrofit that replaces the interior side of an existing deadbolt, similar in concept to the August lock. It is a reasonable starting point if you want app and voice control without spending flagship money. As with any retrofit, confirm your existing deadbolt is compatible before ordering.
Who Should Avoid the Top Pick
Skip any lock that only lists a 1-3/8 inch to 1-1/2 inch door range, since those are aimed at thin interior or hollow-core doors and will not clamp properly on a solid thick exterior door. Also avoid no-name marketplace deadbolts with vague thickness claims, because replacement parts and warranty support are often nonexistent.
Before You Buy
Measure your door thickness at the edge, the backset from the door edge to the center of the bore hole, and the bore hole diameter. Check whether your door has a standard cylindrical prep or a mortise pocket, and confirm the lock includes hardware for your thickness or sells an extension kit. If you rent, get landlord approval before modifying the door.
FAQs
Can a smart lock fit a 2 inch thick door?
Most residential smart deadbolts top out at 1-3/4 inches. Doors thicker than that usually need commercial-grade hardware, a specialty extension kit, or a retrofit lock that reuses the existing deadbolt.
Do I need a hub for a smart lock on a thick door?
Not necessarily. Many current models, including the Schlage Encode Plus and Kwikset Halo Touch, have built-in Wi-Fi. Others rely on Bluetooth, Thread, or a separate hub for remote access.
Will a smart lock work on a metal or fiberglass door?
Yes, but check the door prep and thickness. Metal and fiberglass doors often have different internal structure, and some locks include adapters or require a specific mounting plate.
What is the difference between a retrofit and a full replacement smart lock?
A retrofit keeps your existing exterior keyed cylinder and replaces only the interior mechanism. A full replacement swaps the entire deadbolt, including the exterior keyway.
How do I know if my door is too thick for a smart lock?
Compare your measured door thickness against the manufacturer's published range. If your door is thicker than the maximum listed, look for an extension kit or choose a different model.
Are smart locks for thick doors more expensive?
Not always. Standard-thickness smart locks and thick-door compatible models often share the same price. The cost goes up mainly when you need commercial-grade hardware or specialty extension parts.
Our verdict
For most thick residential doors up to 1-3/4 inches, the Schlage Encode Plus offers the best mix of security rating, built-in Wi-Fi, and Apple Home Key support. If you want to keep your existing exterior hardware, the August Wi-Fi Smart Lock is the easiest retrofit, while the Level Lock Plus is the choice for a nearly invisible install. Measure your door first, because thickness and backset decide which of these will actually fit.