August Wi-Fi Smart Lock 3rd Gen Pro Review (2026): Z-Wave

Why you should trust this review

I installed this lock myself at retail on a real deadbolt and lived with it, rather than testing it on a bench for an afternoon. August did not provide a sample and there is no arrangement behind this review. The lock saw daily use for six months across three people in the household, paired simultaneously to both Apple Home and a SmartThings hub, which is exactly the mixed-ecosystem setup that exposes integration problems.

A smart lock is a security device on your front door, so the things that matter, reliability, whether the geofence actually fires, how long the batteries really last, are the things that only show up over months of real use. A quick install-and-photograph review tells you nothing about whether DoorSense stays accurate or whether the Z-Wave automations stay snappy. I leaned on six months of daily use plus the large body of owner reviews to ground this rather than first impressions.

How we evaluated

I installed the lock on an existing deadbolt, which is the whole point of a retrofit, and tracked the install ease and fit. I paired the Z-Wave Plus radio to SmartThings and verified both the automation latency and the range, since Z-Wave is the reason this particular model exists. I tracked DoorSense open-and-closed alerts across a full month to confirm it was distinguishing a closed door from a merely locked one reliably.

I tested the geofence auto-unlock in both suburban and urban settings, because that feature behaves very differently depending on your environment. And I logged battery life through to the first AA replacement so I could give a real number rather than a manufacturer estimate. I also confirmed that HomeKit, Alexa, Google, and SmartThings all worked together rather than fighting each other.

Z-Wave Plus: the reason this model exists

Z-Wave Plus is the single feature that makes the 3rd Gen Pro worth choosing over its newer sibling, and it works exactly as it should. Paired to SmartThings and Ring Alarm, it joined cleanly and the automations fired with low latency, which is the practical advantage of a dedicated mesh protocol over leaning on Wi-Fi for everything. Z-Wave is more efficient and longer-range than Wi-Fi alone, and in a home already built around a hub, that integration is the whole game.

This is genuinely rare. Most retrofit smart locks have abandoned Z-Wave in favor of Wi-Fi or newer protocols, so if you have invested in a SmartThings, Ring Alarm, or Hubitat hub and want a lock that speaks its language natively, this is one of very few options. That is the precise audience this lock is for, and for them it is close to the only game in town.

DoorSense: the underrated feature

DoorSense is the feature I came away most impressed by, and it is the one buyers tend to overlook. It is a small magnetic sensor that mounts on the door frame and tells the app whether the door is actually closed, not just whether the bolt is thrown. That distinction matters more than it sounds: without it, a smart lock will happily report locked while the bolt is sticking out into open air because someone left the door ajar.

Across a month of tracking, DoorSense caught exactly that scenario reliably and alerted accordingly. It is the right way to handle smart-lock notifications, and it turns a lock that knows its own bolt position into a lock that knows the actual state of your door. Most competing retrofit locks skip this entirely, which makes it a real point in August’s favor and a feature I would not want to give up.

The Connect bridge and integrations

Wi-Fi on the 3rd Gen Pro comes via the included Connect bridge rather than being built into the lock, and this is the clearest difference from the newer 4th Gen, which has Wi-Fi onboard. You need the bridge plugged in for remote unlock and voice control over Wi-Fi, though if you only need Z-Wave hub integration, the bridge is optional. It is included in this Pro bundle, so it is not an extra purchase, but it is one more thing taking up an outlet, which is a fair knock.

On integrations, the lock delivered. HomeKit, Alexa, Google, and SmartThings all worked out of the box and coexisted without conflict across my six months, which is not something every smart lock manages in a mixed-ecosystem home. The one feature that was inconsistent was geofence auto-unlock, which was hit-or-miss in dense apartment settings, a limitation of phone-based geofencing generally rather than a flaw unique to this lock.

Install, battery, and the bulk

Installation is the easiest part of owning this lock and the best argument for the retrofit design. The puck installs on the interior side of your existing deadbolt only, so you keep the original cylinder, the exterior hardware, and your physical keys. From the hallway, a renter’s door looks completely unchanged, which is exactly what makes this a renter-friendly choice. The install took minutes and required no replacement of any exterior hardware.

Battery life landed around four to five months on a set of four alkaline AAs with both Z-Wave and Bluetooth radios active, and lithium AAs stretch that meaningfully further. The real downside is physical: the interior puck is bulkier than the 4th Gen and sticks out a few inches from the door. It is not unsightly, but if a slim interior profile matters to you, the newer model is the better-looking choice. That bulk is the price of the Z-Wave radio inside.

Who should buy the August 3rd Gen Pro?

Buy it if you run a SmartThings, Ring Alarm, or Hubitat Z-Wave hub and want a lock that integrates natively, if you want a renter-friendly retrofit that keeps your existing keys and hardware, or if you value DoorSense confirming the door is genuinely closed. For a hub-based smart home, this is the standout retrofit choice.

Skip it if you want the slimmest possible interior puck, where the 4th Gen is the better-looking pick, if you do not want a separate Connect bridge occupying an outlet, or if you specifically want a built-in keypad on the exterior, which this lock does not offer. If you have no Z-Wave hub at all, the newer model’s built-in Wi-Fi makes more sense for you.

The verdict

The August 3rd Gen Pro is the retrofit smart lock I recommend to anyone whose smart home runs on a Z-Wave hub, because it is one of the only options that speaks Z-Wave Plus natively while keeping your deadbolt, keys, and exterior untouched. DoorSense is a genuinely useful feature that most competitors skip, the integrations across HomeKit, Alexa, Google, and SmartThings all held up over six months, and the install is effortless. The honest caveats are the bulkier interior puck and the separate Connect bridge, both of which the newer 4th Gen improves on by dropping Z-Wave. So the choice is clean: if you have a Z-Wave hub, this is the one to buy. If you do not, the 4th Gen’s slimmer, bridge-free design is the better fit.