Nuki Smart Lock Ultra vs Hikvision DS-KIS603-P(B) Review

Smart home entry is one of those categories where getting the wrong product doesn't just frustrate you — it leaves you locked out, or worse, locked in. The Nuki Smart Lock Ultra and the Hikvision DS-KIS603-P(B) are both serious contenders for upgrading your front door, but they're solving fundamentally different problems. One is a keyless lock retrofit; the other is a full video intercom system. The real question is: can they work together, and which one should anchor your setup?

A real-world Reddit thread from a user trying to connect the Nuki Ultra to the Hikvision intercom sheds light on exactly this scenario — and it's a useful lens for understanding both products.

Nuki Smart Lock Ultra

What It Does Well

The Nuki Ultra is built for people who want keyless convenience without ripping out their existing lock cylinder. It fits over your current euro cylinder and motorizes the thumb-turn — installation takes under three minutes if you've done it before. The app-based access, auto-lock, and remote unlock via the Nuki app are all genuinely polished. It supports Matter and Thread, meaning it plays nicely with Apple HomeKit, Google Home, and Amazon Alexa without needing a proprietary bridge (though the Nuki Bridge extends Bluetooth range for remote access).

For shared spaces — Airbnbs, small offices, rental apartments — the ability to generate time-limited digital keys and manage access logs remotely is a genuine game-changer. Battery life is strong, and the lock gives low-battery warnings well in advance.

Where It Falls Short

The Nuki Ultra is a lock, not a doorbell or intercom. It has no camera, no two-way audio, and no way to see who's at the door. That's a deliberate product decision, not an oversight — but it means you'll need a separate video solution if you want to vet visitors before letting them in. Integration with existing intercom systems like the Hikvision unit is possible but not plug-and-play; it typically requires a relay module or third-party automation to bridge the two systems.

It also lives and dies by your smartphone and Wi-Fi/Bluetooth connection. If your phone dies or the app misbehaves, having a physical backup key is essential — not optional.

Hikvision DS-KIS603-P(B)

What It Does Well

The Hikvision DS-KIS603-P(B) is a proper IP video intercom kit: outdoor camera unit, one or two indoor monitors, and PoE-powered infrastructure. The image quality from the outdoor unit is a clear step above most consumer video doorbells — Hikvision's camera sensors are their heritage, and it shows. You get two-way audio, video recording, and the ability to buzz open an electric strike or gate directly from the indoor monitor.

For households with multiple indoor screens — say, a ground floor and an upstairs unit — this system genuinely earns its complexity. It's also wired, which means no battery anxiety and no Wi-Fi dropouts at the door. Installers and security-conscious buyers will appreciate the professional-grade reliability.

The system supports remote viewing via the Hik-Connect app, so you can see and speak to visitors even when you're not home. Combined with a Nuki lock on the door, you'd have a complete see-it-and-open-it remote entry workflow — which is exactly what that Reddit user was trying to build.

Where It Falls Short

This is not a weekend DIY project. Running PoE cabling, configuring IP addresses, and integrating with smart home platforms requires real effort — and potentially a professional installer. The interface on the indoor monitor is functional but dated-feeling compared to modern smart home apps. Smart home integration is limited compared to consumer-grade alternatives; HomeKit support, for instance, is not native.

The system is also overkill for a single-family home where a $100 video doorbell would do 90% of the job. You're paying for reliability, multi-unit support, and professional-grade hardware — if you don't need those things, the value case weakens significantly.

Side-by-Side Comparison

Feature	Nuki Smart Lock Ultra	Hikvision DS-KIS603-P(B)
Primary function	Keyless smart lock	Video intercom system
Installation complexity	Low — DIY, no wiring	High — requires PoE cabling
Camera / video	None	Yes, full HD outdoor camera
Remote unlock	Yes, via app	Yes, via app + indoor monitor
Smart home compatibility	Matter, Thread, HomeKit, Alexa, Google	Hik-Connect app, limited integrations
Power source	Battery	Wired PoE
Multi-unit / apartment support	No	Yes (multiple indoor screens)
Keeps existing key cylinder	Yes	N/A
Best for	Renters, Airbnb hosts, smart home enthusiasts	Multi-unit buildings, security-focused installs

The Verdict: Different Tools for Different Jobs

These two products aren't really competing — they're complementary. The ideal setup for a security-conscious homeowner is both: Hikvision handling the "see and speak" layer at the door, Nuki handling the actual locking and unlocking. That's exactly the integration the Reddit user was chasing, and it's achievable — though it requires some automation glue (a relay on the Hikvision unit triggered by Nuki, or vice versa via a smart home hub).

If you have to pick just one:

• Choose the Nuki Ultra if you're a renter who can't rewire anything, an Airbnb host managing remote access, or someone already invested in a Matter-based smart home ecosystem. It's the more versatile, DIY-friendly, and ecosystem-compatible choice.
• Choose the Hikvision DS-KIS603-P(B) if you own your property, need a professional-grade video intercom for a building with multiple units, or want wired reliability that a Wi-Fi doorbell can't match. Budget for installation help unless you're comfortable running Cat6.

Frequently Asked Questions

Q: Can the Nuki Smart Lock Ultra work with the Hikvision DS-KIS603-P(B) intercom?

A: Yes, but it requires additional configuration — typically a relay module on the Hikvision unit or a smart home automation hub to bridge the two systems. It's not plug-and-play out of the box, but it is a known and achievable integration.

Q: Is the Nuki Ultra easy to install without a professional?

A: Yes. It mounts over your existing euro cylinder thumb-turn with no wiring required. Most users complete installation in under 10 minutes.

Q: Does the Hikvision DS-KIS603-P(B) require a professional installer?

A: For most homes, yes. The system uses PoE (Power over Ethernet) cabling and involves IP configuration. It's manageable for experienced DIYers, but not a casual weekend project.

Q: Does the Nuki Ultra work with Apple HomeKit?

A: Yes. The Nuki Smart Lock Ultra supports Matter and Thread, giving it native compatibility with Apple HomeKit, Google Home, and Amazon Alexa.

Q: Which product is better for a rental apartment?

A: The Nuki Ultra, without question. It preserves the existing lock cylinder, installs without any permanent modifications, and can be removed when you move out. The Hikvision system requires structural wiring and is better suited for owned properties.

— Home Lead Editor, CPrice