The catch
Aqara Smart Lock U50
Lacks UWB and fingerprint access.
Side by side
Aqara U50 vs U400: U50 already accepts home keys, and U400 adds supported hands-free approach entry
Quick verdict
U50 gives you keypad and Home Key entry on replaceable AA batteries. With U400 you also get compatible-device UWB hands-free access, fingerprints and native Matter over Thread.
Before you buy
Why, and what it costs you
UWB hardware isn’t justified by Home Key alone
The tap-to-unlock action is already supplied by U50.
Where this comes from
Home Key works on both. What U400 adds in convenience is approach-based UWB and fingerprint access, which gives a buyer who wants only tapping less functional reason to step up.
The catch
Aqara Smart Lock U400, Black
Specific Apple hardware is required for UWB.
Aqara Smart Lock U50
- Why pick it
- Your routine already works with a deliberate Home Key tap.
- You would rather replace common AA batteries than charge a pack.
- The catch
- Lacks UWB and fingerprint access.
Aqara Smart Lock U400, Black
- Why pick it
- Hands-free entry appeals to you, and you own a compatible UWB Apple device.
- Fingerprints as a further everyday access method appeal to you.
- The catch
- Specific Apple hardware is required for UWB.
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What this page compares
Aqara U50 and U400 go head to head on Home Key, UWB hands-free entry, fingerprints, battery care and the hubs a complete installation needs.
U50 gives you keypad and Home Key entry on replaceable AA batteries. With U400 you also get compatible-device UWB hands-free access, fingerprints and native Matter over Thread.
Which one fits
Pick the situations that sound like you
Hands-free UWB entry is required
Only with compatible devices and home infrastructure can U400 meet this.
- Aqara Smart Lock U50
- Not suitable
- Aqara Smart Lock U400, Black
- Depends
Home Key tapping is all you require
The deliberate tap action works on both.
- Aqara Smart Lock U50
- Similar
- Aqara Smart Lock U400, Black
- Similar
A fingerprint reader is required
U400 alone includes one.
- Aqara Smart Lock U50
- Not suitable
- Aqara Smart Lock U400, Black
- Better fit
You prefer replacing AA batteries to charging
AA cells power U50. U400 runs on a rechargeable pack.
- Aqara Smart Lock U50
- Better fit
- Aqara Smart Lock U400, Black
- Not suitable
In practice
Differences you will notice
UWB hardware isn’t justified by Home Key alone
The tap-to-unlock action is already supplied by U50.
How we worked this out
Home Key works on both. What U400 adds in convenience is approach-based UWB and fingerprint access, which gives a buyer who wants only tapping less functional reason to step up.
Even native Matter depends on infrastructure
Moving to U400 changes which hub type is required. It doesn’t eliminate every hub.
How we worked this out
For Matter, U50 goes through an Aqara Zigbee bridge. U400 uses Thread and needs the compatible controller and border router that ecosystem requires.
A phone can cancel out the upgrade benefit
With an unsupported phone, the UWB reason to choose U400 is gone.
How we worked this out
UWB access depends on compatible Apple hardware. U400 keeps fingerprint and keypad access, but don’t assume its headline hands-free feature works for every device in the household.
Option A
Aqara, DL-D05D
Smart Lock U50
This keypad deadbolt supports Apple Home Key and comes with physical backup keys. Adding a Zigbee hub extends it to remote access and smart-home routines.
- Best for
- Apple Watch users who can do without a fingerprint reader
Facts we checked
- The manufacturer estimates up to six months on the four AA batteries that power the lock.
- Entry works through Apple Home Key, the keypad, Bluetooth app access or physical keys.
- The lock locks itself after the door closes, aided by a built-in gyroscope.
- IPX5 is the water-resistance rating of the exterior.
Option B
Aqara, DL-D06E
Smart Lock U400, Black
Fingerprint access, Apple home key and UWB approach unlocking on supported devices come together in this Matter-over-Thread deadbolt.
- Best for
- A household with a suitable Thread controller plus a compatible phone or watch
Facts we checked
- Entry options the manufacturer lists are fingerprint, keypad, mechanical key, NFC and supported wallet.
- You charge the rechargeable battery through the interior USB-C port.
- An internal gyro handles door-close auto-lock, and the exterior panel is rated IP65.
- The Amazon model selected is the DL-D06E, rather than a hub bundle.
Spec by spec
Where they really differ
| Spec | Aqara Smart Lock U50 | Aqara Smart Lock U400, Black | In practice |
|---|---|---|---|
| Hands-free approach unlocking | No UWB entry | UWB entry with supported Apple devices | The hands-free benefit of U400 hinges on the exact phone or Watch and home setup. |
| Fingerprint entry | Not supported | Supported | Users of U400 have an alternative to a code or Apple device. |
| Smart-home transport | Zigbee with Aqara Matter bridge | Native Matter over Thread | Connected features on U400 still call for an appropriate Matter controller and Thread border router. |
| Power | Four replaceable AA batteries | Rechargeable battery pack | Maintenance shifts from replacing cells to recharging a pack. |
| Exterior rating | IPX5 | IP65 | A specified dust-protection level is added by U400. Water resistance is documented for both. |
Trade-offs
What each pick costs you
With Aqara Smart Lock U50
- A compatible hub is what remote Aqara features depend on.
With Aqara Smart Lock U400, Black
- Plan for rechargeable-pack care and for Thread infrastructure.
Change of plan
When the answer changes
Hands-free entry matters, and your exact Apple device supports UWB
Go with Aqara Smart Lock U400, Black. The extra hardware now answers a daily requirement.
Tapping with Home Key is enough, and you want AA power
Go with Aqara Smart Lock U50. U50 covers both needs and skips the care a rechargeable pack requires.
UWB is expected from an unsupported phone
Neither model fits. That specific phone’s hands-free UWB routine isn’t something either can provide.
Decision guide
How to decide
U50 is the lock for keypad and Home Key entry on replaceable AA batteries. U400 is for compatible-device UWB hands-free access, fingerprints and native Matter over Thread.
Begin with the exact devices
Look at the supported iPhone and Watch list before you pay for hands-free access. UWB support cannot be inferred from an Apple logo alone, and Home Key tapping is a separate feature.
Everyday entry against extra methods
When a tap or PIN works for everyone, U50 is sufficient. U400 becomes more compelling if one person wants UWB while another prefers a fingerprint.
Battery upkeep
AA batteries on the U50 are familiar and easy to keep in stock. The U400 asks you to follow a charging routine. Whichever battery system you choose, keep the supplied mechanical fallback accessible.
What this page can’t tell you
- Firmware and supported-device lists can change over time, and no field test of UWB range or unwanted unlock behavior is claimed.
By the numbers
What the data shows
What we found across the smart locks we compare, plus the checked facts behind each finding.
How many fit
Only 1 of the 25 models checked meet every need here: “Get in by tapping my phone or watch”, “Walk up and let the door unlock itself”, “Use a fingerprint to unlock”, and “Base the setup on Matter”.
1 model fits, out of 25 checkedShow the facts and the math
How we countedThe count uses each product's current fit ratings for “Get in by tapping my phone or watch”, “Walk up and let the door unlock itself”, “Use a fingerprint to unlock”, and “Base the setup on Matter”. A need with no documented match is not counted.
| Product | Needs it meets | Facts we checked | Sources |
|---|---|---|---|
| Aqara Smart Lock U50 |
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| Aqara Smart Lock U400, Black |
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Ready to buy
See today’s price and what owners say
Open either model on Amazon for the current price, customer reviews and delivery options.
Aqara Smart Lock U50
Your routine already works with a deliberate Home Key tap.
See price & reviews on AmazonAqara Smart Lock U400, Black
Hands-free entry appeals to you, and you own a compatible UWB Apple device.
See price & reviews on AmazonEach link opens in a new tab.
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