Aqara Smart Lock U400 vs Nuki Smart Lock Ultra

Aqara Smart Lock U400 wins with its lower price, IP65 outer panel, built-in fingerprint, keypad, NFC, Home Key and UWB unlocking, and guest password toolkit. Nuki Smart Lock Ultra counters with a higher rating, 2-year warranty and native Google and Alexa support.

Exterior hardware. The Aqara mounts a weatherproof panel with biometrics and keypad outside and unlocks hands-free via UWB with an iPhone or Apple Watch. The Ultra is a sleek interior-only motor over a European cylinder; keypad and fingerprint are paid accessories.

The Nuki Smart Lock Ultra, which owners call the brand's best lock yet: fast, compact and premium with only minor install quirks. The Aqara Smart Lock U400 is new for 2026 with strong early praise for its UWB but unproven long-term reliability.

The Nuki Smart Lock Ultra works natively with Google Home, Alexa, HomeKit, SmartThings, Home Assistant and Matter. The Aqara Smart Lock U400 covers HomeKit, Home Assistant and Matter over Thread, needing an Aqara hub for Google Home and Alexa.

Choose Aqara Smart Lock U400 for the most complete and weatherproof keyless door at the lower price, with UWB approach-unlock as the headline for iPhone and Apple Watch households.

Choose Nuki Smart Lock Ultra for the finest European-cylinder retrofit: better-rated, fast, discreet and natively integrated everywhere, backed by a 2-year warranty, if you accept accessory costs for keypad entry.