Ultion Nuki smart lock review: simple to fit and secure

The Ultion Nuki smart lock can be fitted on most doors and makes locking and unlocking your door effortless

Ultion Nuki Smart Lock
(Image credit: Ultion Nuki)
T3 Verdict

The Ultion Nuki smart lock is a simple and effective way to make any door lock smart. The unit attaches to the inside of your regular lock, so it’s not obvious from the outside and while not as slick as some, it’s affordable and easy to fit. Once in place, you’ll never want to go back to keys.

Reasons to buy
  • +

    Easy to install on just about any door

  • +

    Compatible with a wide range of accessories

  • +

    Looks standard from the outside

Reasons to avoid
  • -

    Motor is loud and slow

  • -

    Requires bridge for Wi-Fi connection

  • -

    Quite bulky on the door

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In a world of technology where we can talk to our TVs, have our lights come on when we enter a room and vacuums that clean by themselves, it amazes me that we still use keys to open doors. Simple pieces of steel, cut with precision to fit into a lock and manually turn the mechanism – it's archaic. Smart locks are the simple solution to this. 

Replacing your ancient technology (modern locks date back to the 18th century) with one of the best smart locks allows you to open your door using a range of options, from a simple keypad to an app or merely showing up to the door. It’s liberating, it’s mostly easier to operate and it’s actually more secure. 

Nuki offers a range of smart locks that have two distinct advantages. Firstly, they can fit on almost any door, and install in minutes. And, secondly, thanks to their modular design, they can be very affordable. I tested the Ultion Nuki Smart Lock which retails at £259. This mounts on the inside of your door, replacing the turny bit that you’d normally bolt your door with. It’s designed to fit a wide range of door locks, and can even handle multi-point locks and locks that need a key to lock. 

For my installation, I chose the Ultion Nuki Smart Lock kit which includes a Ultion 3 Star Plus cylinder, the Nuki Keypad and the Nuki Bridge to connect to my home network. The total came to £399, which is still significantly cheaper than some smart locks.

Ultion Nuki Smart Lock

The Ultion Smart Lock with handle

(Image credit: Future)

Installing the Ultion Nuki Smart Lock

There’s an installation checker on the Nuki website to ensure that the smart lock will work on your lock, but in most cases, the answer is yes. I had what looked like a fairly non-standard bolt lock on my door, but the checker told me all would be fine if I also changed the cylinder for a compatible one. 

For the actual installation process, I opted for the hands of a professional and used one of its installation partners but on most doors, you should be able to easily install it yourself – I would certainly be comfortable doing so, having watched this time. My new cylinder slid into place where the old one sat, and then rather than reattaching the back of the lock, the installer screwed the Nuki holder into place (or can also choose to use the strong adhesive but it is more difficult to take off again). The Nuki device then just clips into place, slotting the end of the cylinder into it. 

Once the device is mounted on the door, you activate it via the Nuki app. This is a Bluetooth connection between your phone and the device, which connected easily for me. Once linked, the Smart Lock learns the movement of the lock, seeing how many turns it takes to fully extend the bolt, and then gives you a range of options, such as auto locking and a pin to access. 

Installing the accessories is just as easy. The app lets you choose the accessory from the list, searches for it and then links it to your account. The keypad allows you to not only set a master code for entry but also set individual codes for users, as well as setting times for entry. This is handy if you want to give a code to a dog walker or cleaner – or family member. 

Ultion Nuki Smart Lock

(Image credit: Future)

Ultion Nuki Smart Lock accessories and keys

In addition to the keypad, which can be easily stuck or screwed to a surface within Bluetooth range of your front door, I opted for the Bridge unit. While there is a Ultion Nuki Plus which includes Wi-Fi, the standard model is Bluetooth only, so requires a bridge unit to connect to your smart home and unlock the door from more than a few metres away. 

Like the keypad, the bridge is easy to set up, and will just then ask for your home network details to connect to the Wi-Fi once it is synced to your smart lock. If you want to do more than just use your phone or keypad to unlock your door, the bridge is very useful. Without it, you can’t open the door remotely, or control any of the other settings without being in range. 

For the compatible cylinder, I had a modified version of the Ultion 3 Star Plus installed (this comes with the Smart Lock and Bridge for £399), which is a secure diamond lock and comes with a £2000 security guarantee. The keys for this are 60% thicker than standard keys and can only be duplicated with permission, once registered. Ultion also offers a KeyTag, which is a key that is compatible with Apple’s Find My, allowing it to be tracked and play a sound if lost. 

Ultion Nuki Smart Lock

(Image credit: Future)

Using the Ultion Nuki Smart Lock

Once the Ultion Nuki Smart Lock is set up there’s very little to worry about. When you reach the door, you can open the app on your phone and swipe to open the lock. Or you can set the auto-unlock function so that as soon as you’re in range, it will unlock automatically. Personally, I love having the keypad option, and use that for unlocking more than anything else. However, there is no zero key on the keypad, so you might need to rethink any standard passcodes you use. 

One of my favourite features of the Ultion Nuki Smart Lock is the auto-lock feature. You can set this for a range of times, after which the device will automatically lock itself. This is useful if you regularly forget to lock your door, which I used to do. And I know it won’t lock me out, as I still have the keypad outside to unlock it if I need it. 

There’s a button on the Smart Lock which can be used to lock and unlock through a series of presses. You can also set it to smart mode so that a single press will change to the opposite state (lock when it’s unlocked or unlock when it’s locked). 

The one thing I found is that particularly the unlocking process feels a little slow. It’s probably no more than about three seconds to lock or unlock, but when you’re rushing to open the door, that can feel like an age. While you can reduce the amount the lock turns in the optimisation, this will depend on your lock. Also, the motor itself is pretty loud. I’m constantly startled when I hear it auto-locking from the other side of the apartment. You certainly wouldn’t want to use it to sneak in late at night, as you’d probably wake someone up. Of course, it’s silent if you use the key, so there is that. 

Ultion Nuki Smart Lock

(Image credit: Ultion Nuki)

Should I buy the Ultion Nuki Smart Lock?

As an affordable way to change your regular lock into a fully functioning smart lock, the Ultion Nuki Smart Lock is great. It’s easy to install and you can very quickly have an easier and more secure way of unlocking your home – or wherever you install your lock. I feel that to really get the most out of this system, you need to opt for the bridge accessory, in which case the Plus model, which costs £120 more, is probably a more sensible choice. However, having them separate means you can choose whether or not you use the Wi-fi option, and save the batteries in the unit for driving that motor. 

I’d love to see a slightly slimmer, faster and quieter version of the Ultion Nuki Smart Lock but for the money, this is a great option. I haven’t used my keys once since installing the device, and I’m certainly not going back. 

Ultion Nuki Smart Lock

(Image credit: Future)

Also consider

If you want the Wi-Fi features of the Nuki bridge, the Ultion Nuki Smart Lock Plus is probably the model for you. For £379, this not only includes Wi-Fi built into the device but comes with a rechargeable power pack, rather than AA batteries, and is available in a choice of black or white with an aluminium lock ring that gives it a more premium feel. 

The Yale Linus Smart Lock works on a similar premise to the Ultion Nuki, attaching to the inside of the door. At £220, the Linus is slightly cheaper than the Nuki and still requires an adjustable cylinder for most locks and a Wi-Fi bridge – however, these accessories are also cheaper. 

Mat Gallagher

As T3's Editor-in-Chief, Mat Gallagher has his finger on the pulse for the latest advances in technology. He has written about technology since 2003 and after stints in Beijing, Hong Kong and Chicago is now based in the UK. He’s a true lover of gadgets, but especially anything that involves cameras, Apple, electric cars, musical instruments or travel.