Aqara U400 from a locksmith perspective

Let me begin by saying that I am a professional locksmith in the industry for 15 years. In that time I have installed nearly every type of smart lock you could imagine.

For many years I had the “industry” mentality that if it wasn’t made and designed by a well known brand within the industry… it wouldn’t perform to my rigid expectations. As a locksmith sometimes the customer will provide their own lock to be installed. So I’ve come across many brands that I’d never heard of. Yet the quality of the build seemed at par with the residential smart locks from those other well known brands… and as far as smart features… the customer would be excited to explain the great ways it would help them simplify their lives!

In my own home… I had installed a Schlage smart lock that worked on Zwave that I used for many many years. But I felt like it was time to upgrade. I also wanted to explore some of the great new features available. I knew that I wanted something that would work with HomeKit so that my 12 yr old autistic son could use his phone as a key. I wanted to try two devices and decide which one best suited my needs.

The two choices were the Aqara U400 and the Thorbolt X1. Both devices offered the home key compatibility I required… but Aqara included the new UWB compatibility that seemed very intriguing to me… and a perfect option for my son… if it works. Installation was simple for both devices (again professional locksmith) but setup was a bit more challenging on the Aqara device (issue with pairing to HomeKit through Aqara app. Responding unable to detect thread network) however…I was able to complete the pairing through the HomeKit app itself.

Now… as for functionality… the U400 outperformed the X1 in its spreed of response and more importantly… its throw was stronger and smoother than the X1 by far! As for the UWB compatibility I couldn’t be happier! It is a game changer! I may have wanted it to simplify my son’s life… but it has without a doubt helped me every single day since I’ve installed it! So… as a professional locksmith… my opinion is… BUY IT!!!

You’ll be so glad you did!

16 Likes

I’ve been waiting so long for other options than Yale for HomeKit support! Thanks for flagging the product!! How is battery life?

4 Likes

Battery is rechargeable with usb-c type cable. I’ve yet to recharge it myself… currently 68% during an extremely cold winter in Michigan… so I’d say it’s pretty good so far! But I will report back on battery life as time goes on.

4 Likes

Battery Life so far for me in Georgia not as cold as Michigan charged to 77% in January and have only used 11% so I believe battery is not an issue. I am using a portable battery pack to charge the lock with the battery installed. The lock seems to work well, when charging but slow. Charging this way does not change the operations of the Lock.

:1xabxh6ezyjfydcqudk6zz_173252: :orcw0m2x379og2tctldusc_173252:

3 Likes

Charged last night form 66% to 95%
Anker Laptop Power Bank, 25,000mAh Portable Charger.
This is the first time I have charged the U400 lock sense I installed it on 14 Jan 2026.

:1xabxh6ezyjfydcqudk6zz_173252: :orcw0m2x379og2tctldusc_173252:

2 Likes

Thanks for this, I have thought about adding a smart lock to my home for a while but I’ve been hesitant, worried about the security of them. But after looking at the features of the U400 I may just go ahead and give it a try.

I’ve been quite happy with the performance of my Aqara doorbell. Not perfect, but good enough.

2 Likes

@Integralocksmith Since your a locksmith…any idea what core could be purchased to make this lock compatible with my existing kwikset locks that the rest of my house uses?

3 Likes

You’ll need a kwikset key in knob cylinder set to your house key. You’ll need to remove the tailpiece from the existing cylinder to place it on the new kwikset cylinder before installing the cylinder into the lock.
Also… be sure that the new cylinder is the same length as the original to fit properly.
I hope this helps you.