Aqara Smart Lock U400 vs Nuki Smart Lock Pro comparison

Updated June 2026

Data from Amazon and official Aqara and Nuki sites.

2026 verdict

Aqara Smart Lock U400 wins on weather resistance, unlock methods and password features. Its outer panel is rated IP65 for dust and heavy rain, and it builds in fingerprint, touchscreen keypad, NFC, Apple Home Key and UWB hands-free unlocking with one-time, periodic and anti-peep passwords, where the Nuki keeps entry minimal and sells keypad and fingerprint as accessories. Nuki Smart Lock Pro answers with a lower price, a higher owner rating, a 2-year warranty and broader native integrations including Google Home and Alexa without extra hardware, plus built-in Wi-Fi and its signature minutes-long European-cylinder retrofit with geolocation auto-unlock. Both support Matter, HomeKit and Home Assistant with roughly 6-month batteries. For the most capable front door, the Aqara Smart Lock U400 takes it; refined Euro-door retrofits stay Nuki territory.

Feature	Aqara Smart Lock U400	Nuki Smart Lock Pro	Winner
Price	$269.99	€269.00	Nuki Smart Lock Pro
Rating	4.0	4.3	Nuki Smart Lock Pro
Weather Resistance	IP65	NO	Aqara Smart Lock U400
Integrations	Google Home, Alexa, Apple HomeKit, Home Assistant, Matter	Google Home, Alexa, Apple HomeKit, Samsung SmartThings, Home Assistant, Matter	Nuki Smart Lock Pro
Lock/Unlock System	Remote, Bluetooth, Passcode, Fingerprint, NFC Tag, Apple Home Key, Physical Key	Remote, Bluetooth, Passcode, Fingerprint, Physical Key	Aqara Smart Lock U400
One-Time Password	YES	Keypad required	Aqara Smart Lock U400
Periodic Password	YES	Keypad required	Aqara Smart Lock U400
Anti-peep Password	YES	NO	Aqara Smart Lock U400
Battery Life	6 months	6 months	Tie
Connectivity	Bluetooth, Thread Protocol, Other	2.4 GHz WiFi, Bluetooth, Thread Protocol	Tie
Emergency Fingerprint	NO	NO	Tie
Doorbell	NO	NO	Tie

Winner

Aqara

Aqara Smart Lock U400

$269.99

Buy on Amazon USA

+ Weather Resistance: IP65
+ Lock/Unlock System: Remote, Bluetooth, Passcode, Fingerprint, NFC Tag, Apple Home Key, Physical Key
+ One-Time Password: YES
- Price: $269.99 vs €269.00
- Rating: 4.0 vs 4.3

Nuki

Nuki Smart Lock Pro

€269.00

Buy on Amazon Germany

+ Price: €269.00
+ Rating: 4.3
+ Integrations: Google Home, Alexa, Apple HomeKit, Samsung SmartThings, Home Assistant, Matter
- Weather Resistance: NO vs IP65
- Lock/Unlock System: Remote, Bluetooth, Passcode, Fingerprint, Physical Key vs Remote, Bluetooth, Passcode, Fingerprint, NFC Tag, Apple Home Key, Physical Key

Frequently Asked Questions

Which is better overall: Aqara Smart Lock U400 or Nuki Smart Lock Pro?

Aqara Smart Lock U400 wins with its IP65 panel, built-in fingerprint, keypad, NFC, Home Key and UWB approach-unlock, plus guest passwords. Nuki Smart Lock Pro counters with a lower price, higher rating, 2-year warranty and hub-free Google and Alexa support.

What is the biggest difference between Aqara Smart Lock U400 and Nuki Smart Lock Pro?

Entry hardware. The Aqara puts a weatherproof exterior panel with fingerprint, keypad and NFC on the door and adds UWB hands-free unlocking. The Nuki is interior-only on a European cylinder: sleek and quick to fit, but keypad or fingerprint entry costs extra.

Which integrates more easily?

The Nuki Smart Lock Pro: Google Home, Alexa, HomeKit, SmartThings, Home Assistant and Matter all work natively. The Aqara Smart Lock U400 handles HomeKit, Home Assistant and Matter over Thread, but needs an Aqara hub for Google Home and Alexa.

Do both auto-unlock as you arrive?

Differently. The Nuki Smart Lock Pro uses geolocation to unlock hands-free as you approach with your phone. The Aqara Smart Lock U400 uses UWB precision from an iPhone or Apple Watch, opening the instant you reach the door (a Thread-enabled Apple hub is required).

Who should buy Aqara Smart Lock U400?

Choose Aqara Smart Lock U400 for a fully equipped, IP65-sealed smart door with every unlock method built in, especially in Apple households that can exploit UWB and Home Key.

Who should buy Nuki Smart Lock Pro?

Choose Nuki Smart Lock Pro for a premium, better-rated Euro-cylinder retrofit with native voice assistant support, built-in Wi-Fi, a 2-year warranty and a clean interior-only look.

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