Smart locks: what the standard covers and what it does not

What the standard actually defines#

This is the category where people most often assume Matter is thinner than it is. The door lock cluster is one of the richest in the specification. It defines PIN, RFID, fingerprint and face credentials, users, credential provisioning over the air, weekday, year day and holiday access schedules, an access log, notifications, a door position sensor, unbolting as an action separate from unlocking, and the Aliro provisioning features added in Matter 1.4.

So the standard is not the constraint. Controller implementation is the constraint, and it varies more here than in any other device category.

What stays in the vendor app regardless#

Three things do not cross to any platform, because they are outside the standard entirely:

• Fingerprint enrollment. Registering a finger requires the vendor's app and, usually, physical presence at the lock. Once enrolled, the finger works locally and offline forever, which is the point.
• Camera and doorbell linking. A lock that shows you a video clip when someone enters a code is doing that inside one manufacturer's ecosystem.
• Vendor unlock modes. Passage mode, intent detection, hands-free approach behavior and similar features are each a manufacturer's own design, not a cluster.

This is the same pattern described in what you lose through a bridge and Matter's limitations: the standard carries the function, the vendor keeps the experience.

Aliro, precisely#

Aliro is not Matter, and it is not Apple Home Key. It is a separate alliance standard, released as version 1.0 on 26 February 2026, with its certification program and test suites published at the same time.

What it is: a common credential format and a reader-to-device protocol using asymmetric cryptography, over three transports. NFC for a deliberate tap, Bluetooth LE for a longer-range user-initiated unlock, and Bluetooth combined with ultra wideband for hands-free approach. It works offline, which matters more than any other property on this page.

Why it matters: Apple, Google and Samsung have all committed to carrying Aliro credentials. Until now, phone-as-key has meant picking a wallet and buying a lock licensed for it. Aliro is the first credible attempt at one credential that works across all three.

Matter is the provisioning rail. Matter 1.4 added Aliro provisioning features to the door lock cluster, so the flow is: commission the lock over Matter, provision the Aliro credential through it, then the phone-to-lock transaction happens over Aliro with no cloud and no hub in the path.

Where it stands in practice as of September 2026: ULTRALOQ announced Aliro certification across several of its Latch and Bolt models in May 2026, Nuki's Keypad 2 NFC ships with support, and Schlage has promised it on the Sense Pro later in 2026. Samsung Wallet's Digital Home Key launched on Aliro in March 2026.

Note also that Apple Home Key is proprietary and separate. No Matter cluster provisions it; the lock carries an Apple-licensed secure element and is provisioned through Apple Home, after which the credential lives in Wallet and works offline on power reserve.

Batteries, and the number nobody prints#

Set your expectations from the feature list, not the marketing:

The mechanism is straightforward. A motor moving a bolt is the largest single draw, so lock and unlock cycles per day matter more than protocol. After that, anything that keeps a radio listening (Wi-Fi, ultra wideband ranging, a fingerprint sensor waiting for a touch) sets the floor. A Thread lock is a sleepy device between events only if the manufacturer implemented it that way, and several do not.

Two practical points. Every lock worth buying keeps working when its batteries are low and tells you first, and most have an emergency contact for a 9 volt battery or USB-C. And check whether the lock uses standard cells or a proprietary rechargeable pack, because a pack you cannot buy in five years is a lock you cannot use in five years.

When the network fails#

A lock is the one device where you should think through the failure modes before buying, not after.

• A key still works, on any lock that keeps a keyway. Some do not, which is a deliberate design choice you should make deliberately.
• The keypad still works. Codes are stored on the lock, so a network outage does not stop someone entering a code. This is true even on cloud-dependent locks, and it is the strongest argument for a keypad over a phone.
• Remote unlock stops on almost everything, because remote access is where the cloud lives even in mostly local systems.
• Auto-lock keeps running, since the timer is on the lock.
• Notifications stop, which matters if you rely on "the door was opened at 3pm" rather than on the lock itself.

Run your specific setup through the internet outage audit, and read what still works when the internet goes down for the wider picture.

The security tradeoff, stated plainly#

A smart lock is not obviously less secure than a mechanical one, and it is not obviously more secure either. What changes is the shape of the risk.

What genuinely improves. You stop hiding a key under a rock, you stop giving out copies you cannot revoke, you can grant access for a window of time, and you get a record of what happened. For most households the biggest real risk is an unlocked door, and auto-lock addresses exactly that.

What genuinely gets worse. You add software to a physical barrier, which means firmware updates matter, default settings matter, and a vendor's account security becomes your door's security. A lock with a cloud account is only as good as that account's password and second factor.

What is mostly noise. Sophisticated radio attacks on a certified lock are far down the list of ways a house gets entered. Matter requires timed transactions for lock operations, which bounds a command by a maximum timeout and defeats replay, and Matter locks use per-device credentials rather than a shared key. The realistic threats are a weak account password, a code you gave out and never removed, and a door frame that a screwdriver defeats regardless.

The thing nobody mentions. Most residential doors fail at the frame long before the lock. If you are spending on security rather than convenience, a longer strike plate screw set into the stud is cheaper than any lock on this page and does more.

Renting#

A smart lock is one of the harder renter items, because it usually modifies the door. Three approaches, in order of how well they survive a lease:

1. Interior-only retrofit. A motor that turns the existing thumb turn from the inside. Nothing about the exterior changes, the original key still works, and it comes off with a screwdriver. This is the right answer for most renters.
2. Deadbolt replacement, original kept. Swap the deadbolt, keep every original part in a labeled bag, and reinstall it on the way out. Check the lease first, because in many places changing a lock without permission is a lease violation regardless of how reversible it is.
3. A keypad, not a lock. If the goal is not carrying keys, a lockbox or a keypad handle on an interior door may solve the actual problem without touching the entry.

Smart home for renters covers the rest of the no-drill, no-rewire approach.

How to buy one#

1. Start from your platform, using the table above. If you are on Apple Home and you want guest codes managed centrally, either accept the vendor app or reconsider the platform.
2. Check the connection method, not the brand. Matter over Thread needs a border router, Z-Wave needs a hub with the radio, and Wi-Fi locks generally mean a vendor cloud. The compatibility checker will tell you what happens with your combination.
3. Decide about the keyway deliberately, before you look at models.
4. Check the battery type, and reject proprietary packs unless replacements are actually purchasable.
5. Check whether any feature you want needs a subscription. Some access logs and notification features are paid on some brands.
6. Measure the door. Backset, bore diameter and door thickness eliminate more candidates than any software consideration.