Eufy Security Smart Lock S230 vs Nuki Smart Lock Ultra

The Eufy Security Smart Lock S230 wins overall, with a lower price, tougher weather resistance, longer battery life and every guest-code option built in. The Nuki Smart Lock Ultra still has real strengths: it out-rates the Eufy and offers a longer warranty plus far wider smart-home platform support.

Yes. Among the locks in this comparison, the Nuki Smart Lock Ultra carries the higher owner rating, though the Eufy Security Smart Lock S230 still wins the overall matchup on price, weatherproofing, battery life and built-in guest passwords.

Door type and price tier. The Eufy Security Smart Lock S230 is a more affordable, full US-style deadbolt built around a fingerprint reader, while the Nuki Smart Lock Ultra is Nuki's premium European cylinder retrofit, with hands-free geolocation auto-unlock but no fingerprint reader built in.

Not built in. Passcode and fingerprint entry require Nuki's separate Keypad accessory. The Eufy Security Smart Lock S230 includes both a keypad and a fingerprint reader plus one-time, periodic and anti-peep passwords without any extra accessory.

Buyers who want the more affordable, weatherproof fingerprint deadbolt of the two, with every guest-code type built in and no accessories to add.

Buyers with a European cylinder door who want Nuki's best-reviewed, most refined lock, the widest smart-home platform support, and hands-free auto-unlock, and who are willing to pay a premium and add the Keypad accessory for code or fingerprint entry.