Aqara Smart Lock U300 – A Solid Unit Marred by a Slow Start
The Aqara Smart Lock U300 is a lever-style smart lock designed to enhance home security and convenience. Unlike traditional deadbolts, the U300 features a spring latch mechanism, making it suitable for various doors, including side entries, garage doors, and home offices.
Before we dive into the features (I’ve shared my experience alongside each one), I want to paint a picture of my journey with the Aqara U300. It hasn’t been smooth sailing — but we got there in the end!
Getting Started (a.k.a. The Long Road to Installation)
This journey started back in 2024. And first off, my apologies to Aqara for how long it took — but here at DRN, we do things proper-like. We don’t just open the box and say, “Ooh, that looks nice!”
The first hurdle? My partner. She’s a fan of actual keys and switches that you flick with your finger. And I imagine, in this day and age, she’s not the only one. I wouldn’t call her old-fashioned (at least not to her face!) — maybe just a little tech-skeptical.
We agreed not to install it on an exterior door at first. The fact that we’d only built our house four years ago — and here I was asking to cut a semi-large hole in a door — probably added to her hesitation.
When the lock arrived, it felt solid and well-made, with multiple faceplates, strike plates, and even handy stick-on templates to guide the cuts. Unfortunately, I already had a handle mechanism in the door, so there was no support for my hole saw’s pilot bit. I ended up gluing bits of ply to the door to guide my cut. Bit of a mess, honestly — but I’d do it differently next time!
Installing the lock into a new door would be a breeze. But of course, I had to make things hard for myself.
The Install (and a Bit of Trouble)
I eventually shaped the cavity using a jigsaw and got the lock fitted nicely — both front and back, including the barrel (which I also had to re-drill).
Once everything was physically installed, I powered it up with the included AA batteries. That’s when I noticed the handle was a bit loose and only pulled the bolt back about three-quarters of the way. So, when I shut the door… it locked, and I couldn’t open it. Not ideal.
I managed to get it open again, rechecked everything, and found that there was some play between the handle and mechanism. I reached out to Aqara’s support — which, to me, is a crucial part of testing a product — and they were top class. Diagnosed the issue, sent me a replacement part in a couple of days. Good stuff.
After reassembling, it worked. Or so I thought.
Setup & App Experience
The setup was simple. These iOT and Thread-based devices tend to be. I installed the Aqara Home app on my iPhone 14, tapped the “+” symbol, and scanned the Hub M3 to add it to my Home dashboard. Then I added the Door Lock via its QR code.
Quick aside: my 15-year-old asked, “Can’t anyone just scan that code and add it to their phone?” A fair point — but the code’s on the inside of the locked door. Still, I’ve removed the codes and stored them safely, just in case.
Once set up, the lock worked — mostly. About every second use, I got a “mechanical exception” error in the app logs. Again, I contacted support. Again, they replaced the unit quickly and were very helpful in troubleshooting. Impressive, especially these days when support can be hit or miss.
The Working Unit (Finally)
Now, the lock is working seamlessly.
I’ve added the U300 to Apple Home, set up my thumbprint, and handed out access to family. This isn’t a super-technical review of Thread or iOT — I don’t know enough about that side of things. But here’s what I do know: I thought this would be gimmicky. I expected to hate it.
But I really enjoy using it.
It keeps the kids’ devices locked away. It stores my more valuable equipment. I know who’s gone in and when. If the door’s left open, I get a notification. Simple.
What I Love Most
Access options are where the U300 shines. You can unlock it via:
- Fingerprint Recognition: Stores up to 50 unique fingerprints.
- Apple Home Key: Just tap your iPhone or Apple Watch (even if out of power).
- NFC Cards: High-security NFC support.
- Customisable Passcodes: Including one-time and recurring codes.
- Aqara Home App & Voice Assistants: Remote control and monitoring.
- Physical Keys: Yes, actual keys — as my better half reminded me with a smirk.
Matter over Thread support ensures it plays well with Apple Home, Google Home, and Alexa. I already had a HomePod Mini for Thread, but Aqara also sent their Wisdom Hub M3, which works great.
Auto-locking & Passage Mode are fantastic. I have it auto-lock instantly, but you can delay that up to 2 hours. Passage Mode is perfect for moving furniture or telling someone, “Leave it open, I’ve got printing
Design, Durability & Battery
We got the black version (matches our house hardware). The unit is IPX4 rated — fine for rain — and operates in extreme temperatures. Ours is indoors, so that’s less of a concern.
Battery life? Too early to say, but the app shows battery as “High,” and swapping AA batteries is dead easy. No big worries there.
to do.
Final Thoughts
Yes, this journey started off rocky. But thanks to solid customer support and a good end result, I’m happy — and actually considering another unit for our main exterior door.
At around $400, I think it’s worth the price. The build quality is excellent, and the functionality is genuinely useful.
I’m not giving this one a star rating — feels unfair given the hiccups — but I would buy another. And that probably says more than a number ever could.
A solid unit… just with a bumpy intro.
DRN would like to thank Aqara for providing the review unit, and for their patience and excellent technical support.
