This smart lock offers one too many features for me, but you just might dig it

As if on steroids, smart locks have been advancing in amazing and surprising ways over the last year, with each few months bringing a new “first” to the market. Eufy’s FamiLock S3 Max offers yet another smart lock innovation that would have been unthinkable just weeks ago: It’s the first model we’ve seen that has a built-in, 4-inch video screen on its interior escutcheon, relaying video from a camera mounted on the exterior escutcheon, no secondary device required.

It’s a neat idea but right off the bat, it’s clearly not a lock that’s going to make sense for everyone. Like many homeowners, I have a massive window set into the center of my front door, so having a small video screen that displays what is happening on the other side of that door isn’t going to do me much good. However, those with fully opaque doors—especially apartment dwellers –might find this a much more compelling proposition than a peephole.

Specifications

The Eufy FamiLock S3 Max has a lot going on, and as a result it consumes a huge amount of space. Both interior and exterior escutcheons are enormous, with the exterior measuring 7 x 2.5 inches in size (HxW) and the interior 8 x 3 inches. Both elements are more than 1 inch thick. The full weight of the device is a significant 2 pounds, 11 ounces, although you’ll probably be aware of that only during installation. It carries a weatherization rating of IP65, so according to our IP code decoder, it’s entirely protected from particulate matter, like dust, and that it can withstand blasts of water from a tightened nozzle (but not a pressure washer). Eufy also obtained an ANSI Grade 1 certification, which our ANSI/BHMA guide tells us is the highest rating for physical security.

The list of features on the lock goes far beyond its video capabilities, but that’s where we’ll start. The four-inch display relays video from the front-mounted camera, which captures square-shaped video at a maximum resolution of 1600 x 1600 pixels, with a 180-degree (diagonal) viewing angle. Standard infrared video is built in. Video is stored locally by default on 16GB of non-upgradeable storage. A cloud backup service is available, but it’s certainly not required unless you’re concerned about someone stealing the lock itself. The plan runs $3/month or $30/year for one device or $10/month or $100/year for up to 10 devices. Both plans store a copy of all videos online for 30 days. (These prices however are going up on April 1, 2025.)

The unit also functions as a doorbell, courtesy of a large button that becomes ringed in blue light when motion is detected. There’s no interior chime included with the lock, but you can configure an Amazon Echo device to serve as a chime if you install the appropriate skill. This worked well in my testing.

As far as access goes, the unit has two primary avenues of operation. First, a numeric touch-sensitive keypad supports a maximum of 100 PINs. Second, the unit includes a now trendy palm vein reader, allowing for touchless authentication by simply holding your hand a few inches away from a reader mounted on the top of the exterior escutcheon. The lock can store 50 different palm scans (up to two per user). Lastly, in addition to app-based access, the unit includes a physical keyhole that can be accessed by popping out the doorbell button, although note I found it to be a little difficult to get back into place securely.

The unit is uniquely powered by a rechargeable 15,000mAh battery and four AAA batteries that serve as backups in case the primary cell dies. These are wedged into the interior escutcheon atop the primary cell, which is part of the reason why the interior escutcheon is so large. Eufy says the primary cell should last at least six months, with one additional month of operation provided by the AAA cells in reserve. There is no emergency power port on the exterior escutcheon, so don’t ignore the notifications of the primary battery’s state—at least not for long.

With all of that prologue, we can finally delve into how well all of this works. The short answer, all around, is quite good.

Setup and installation

Christopher Null/Foundry

Physical installation isn’t difficult, but it does take a few small extra steps due to the needs of the video system. As is common, the exterior escutcheon is bolted to an interior frame with two screws, which in turn attaches to the interior escutcheon with an additional four screws. Two electronics cables are needed to connect the two pieces together, although these are easy to properly route and get seated properly. There’s an additional piece on top of the interior escutcheon that houses the video screen, this snaps on without the need for additional hardware, covering up the battery packs. All of this goes together quickly and cleanly, despite the few extra pieces in the mix.

Setup in the revamped Eufy app (no longer called Eufy Security) involves little more than scanning a QR code on the interior escutcheon. Oddly, this is labeled as a Matter code (more on Matter support later), but it also functions directly with the Eufy app. In my testing, the app connected quickly to the lock and I had it onboarded and connected to my 2.4GHz Wi-Fi network (5GHz networks are not supported) in less than a minute.

Christopher Null/Foundry

The Eufy app is a sprawling system that isn’t particularly difficult to navigate, but it does require a significant amount of time to master because it has so many moving parts. The app is now a do-it-all system with separate tabs for “lights,” “security,” “clean,” and “care,” and it handles everything from smart locks to robotic mowers to smart scales and breast pumps. You’ll find the FamiLock in the security section, where a widget with the most recent thumbnail from the lock’s camera can be seen, along with quick access to the lock/unlock icon. Tapping the thumbnail takes you to a larger, live view of the camera, along with quick access to on-demand recording, screenshot, up to 3 “quick responses” that you record with your own voice, and two-way talk. You’ll also get to this screen automatically if someone rings the doorbell and you tap the notification.

Recordings are managed through the Events tab at the bottom of the screen, and they’re presented as a chronological view of all activity—door lock/unlock actions, motion detections, and doorbell rings—with all videos accompanied by a thumbnail. You can set the camera to record on all motion or only when humans are detected (and you can dial the detection range from 3 to 20 feet). The onboard AI does a good job of determining if a human is in the video or not. An activity zone, loitering detection mode, and “leaving detection mode” that notifies you if someone departs are all also available.

Performance

Video quality is fine but nothing earth-shaking. The ultra-wide-angle view makes for quite a distorted view, and unless your visitor is less than a few feet away from the door, I found it was virtually impossible to make out their face. Night vision is solid, in part because of multiple lights on the front of the device that illuminate when motion is detected.Clips loaded quickly throughout my testing and could be easily downloaded without trouble.

User management is tied to individuals, and you can configure each person to have 24/7 access, scheduled access (expiring at a set time or based on time/day of week), or one-time access, using a PIN that you set. Only after a PIN is added are you invited to add up to two palm vein scans for the user, though these are optional. I had no trouble using either PINs or palms to gain entry to the lock, although the lock sometimes struggled with palm scans if my hand was presented at an angle instead of vertically.

Christopher Null/Foundry

Additional features I haven’t yet covered include auto-locking (5 seconds to 3 minutes, schedulable) and configurable wrong-try protection that locks down the device for up to 5 minutes after 3 to 10 wrong attempts. A variety of power-management modes are available as well that let you determine when and for how long to record video. (“Optimal surveillance” will record for up to 60 seconds when motion is detected, while “Balance surveillance” will max out at 20. “Optimal battery life” won’t record on motion detection at all.)

Should you buy the Eufy FamiLock S3 Max?

As noted previously the device supports Matter and can be onboarded directly to a Matter hub by scanning the same QR code on the interior escutcheon. I was able to add the lock to iOS Home by scanning the code, but soon found there’s very little point to doing this, as there’s no support for most of the advanced features of the lock through Matter—including palm vein scanning and any of the video features. If you’re just looking for a Matter lock that lets you assign PINs, there are many more affordable and simpler options around.

Further reading: This review is part of TechHive’s in-depth coverage of the best smart locks.

Lastly, at $400, there’s no way around the fact that the Eufy FamiLock S3 Max is extremely expensive—more than the combined cost of a separate video doorbell and quality smart lock. That said, does work very well considering its complexity; as such, it might make sense for those who prefer a single device and who can make good use of the integrated video screen.

If you do have a window in your door—or sidelights next to it—you might want to consider the Eufy FamiLock S3, instead. It has the same features except for the integrated camera and display, and it costs $50 less: $349.99.