Do I need a smart door lock? The key to a safe and secure home

Prone to losing your keys or tired of fumbling with a deadbolt? The latest smart home technology means you can now go keyless by installing a smart lock on your front door. 

As well as removing the need for a physical key, many smart locks are wi-fi connected, meaning you can grant remote access to guests, double-check your door is locked if you left in a hurry or even let someone in with a voice command through your smart speaker.

But they’re not without their drawbacks, from battery reliance to potential security and insurance considerations. We explain how smart locks work, the pros and cons and highlight some popular models to consider.

How does a smart door lock work?

Smart door locks replace traditional mechanical locks with an electronic alternative, using a motor to turn the deadlock.

With a smart lock, you won’t need to rummage through your bag for your keys. Instead of manually turning a lock, they secure your property using an entry code, biometric recognition like a fingerprint or remotely via an app on your smartphone. Sometimes they also come with a fob or keycard.

Smart locks generally connect to your smartphone and other devices using Bluetooth or wi-fi.

• Bluetooth-enabled locks connect when in proximity to your device. This often means you have fewer features and cannot control the lock remotely.
• Wi-fi locks allow you to see who is entering and exiting your home from an app on your phone and can often provide temporary access to certain people. This can be useful for managing access without needing to hand out spare keys.

5 popular smart door locks

Which? hasn't tested smart locks, so we've rounded up some of the most popular models based on retailer data and search trends.

Yale Conexis L2 Smart Door Lock

We like: Unlock the door with your phone, a key tag or key card

Watch out for: Lift to lock means you still need to lock it manually

This Yale smart lock replaces the entire handle on PVC and composite doors. 

Installation is simple; you should only need a screwdriver. Then, you can unlock it using the Yale Access app or the included key tags or key cards. 

The lock automatically unlocks as you approach, and DoorSense ensures it is securely closed when you leave. However, due to the lift-to-lock mechanism, locking must be done manually, as it can’t be controlled via the app. 

For security, it includes a tamper alarm, two-factor authentication and a three-minute lockdown after multiple failed attempts. It is pick-proof since it has no external keyhole.

Ultion Nuki Smart Lock 2025

We like: Stylish and feature-rich

Watch out for: Fob, keypad, and auto-lock sensor sold separately

The Ultion Nuki replaces your current cylinder, so the underlying lock remains secure even if the smart motor is removed.

The device unlocks the door as you approach and locks it again a few seconds later, so there’s no need to type in a code, find your fob or open the app.

Thanks to a built-in wi-fi bridge, the Ultion Nuki can be controlled by voice and is compatible with Apple Home, Amazon Alexa, Google Home and other smart home systems.

For added peace of mind, it comes with a regular key. However, you will need to purchase the auto-lock sensor, keypad and keyfob separately.

The Ultion Nuki cylinder is BSI Kitemark certified (the highest physical security standard) and it has a £5,000 security guarantee. It’s designed to fit existing doors with 215mm, 211mm and 122mm handle fixings as well as doors with an escutcheon lock. 

No drilling or wiring is needed for installation, so you should be able to do it yourself.

Aqara U200 Smart Door Lock

We like: No drilling required

Watch out for: Needs a separate hub for some features

The Aqara U200 smart lock allows you to unlock your front door by tapping your phone against it, entering a passcode or using the fingerprint sensor. 

You can control it via a smartphone app and create temporary passcodes for visitors. If you have an Apple Watch, you can use that to unlock the door too. It also supports unlocking with a mechanical key as a backup.

A built-in gyroscope can alert you if the door is left open and will automatically lock once you close it. There’s also a Quiet Unlock Mode that minimises motor noise by slowing it down, perfect for early mornings or late arrivals.

Aqara claims the lock can last up to six months between charges. The keypad runs on AAA batteries or can be hard-wired to the front door.

Bold Smart Lock SX-65

We like: Fully keyless front door

Watch out for: Buy the Bold Connect separately for wi-fi connectivity

The Bold smart lock is fully keyless. Your phone becomes the key.

It connects through Bluetooth or wi-fi (although to enable wi-fi connectivity, you'll need the Bold Connect device which is sold separately). 

Set schedules, monitor access logs, and manage permissions through a smartphone app. It can also be controlled by voice or via an Apple Watch. If your phone runs out of battery, you can use the backup PIN or the Bold clicker.

It replaces your existing cylinder and should be simple enough to install yourself. You'll just need a screwdriver and the step-by-step instruction video.

You can fit it on any suitable Euro cylinder, measuring 56mm to 65mm internally and 50mm to 65 mm externally.

Yale Linus Smart Lock L2

We like: Fits over your current Euro cylinder

Watch out for: Not compatible with the lift-to-lock doors

The Yale Linus Smart Lock L2 is a retrofit motor that fits over your existing Euro cylinder on the inside of the door. It’s a non-permanent solution, ideal for renters.

Since the keyhole remains exposed on the other side, your physical key can still be used.

With Matter support, it can work with multiple devices simultaneously, such as an Apple Watch, Amazon Alexa speaker, and Google Nest Hub. It is also compatible with both iPhone and Android devices. 

Are smart locks safe for front doors?

Smart locks offer additional security features to traditional locks because they enable you to monitor them and review activity logs remotely via an app. You can grant access without handing over a key, and revoke it just as easily.

Because wi-fi locks connect to the internet, they could be vulnerable to hacking or technical issues. 

However smart locks often use high-level encryption to secure the connection between the lock and its smartphone app.

Traditional locks can be picked, but if an intruder tries to break into a smart lock by guessing your access code they will often be automatically locked out after too many incorrect attempts. 

To keep your smart lock secure, create a long, unique password, keep the software updated, and where possible, connect it to other security devices such as outdoor cameras and smart security systems. 

If you're looking for more ways to secure your home, take a look at these tips to keep your home safe when you're away. 

How do I install a smart door lock?

Smart locks are generally straightforward to install on your own, with most brands offering step-by-step video tutorials. 

Retrofit locks are the easiest because they attach over your existing deadbolt, meaning you don’t have to remove the old lock and your current keys will still work.

Other smart locks replace the entire deadbolt, which involves installing a new cylinder. This process is slightly more complex and time-consuming. Usually, all you'll need is a screwdriver, though some models might require a drill. While DIY installation is possible, you might prefer to hire a professional if you're unsure.

What are the downsides of a smart door lock?

There are some downsides to using a smart lock over a traditional, mechanical lock. 

• Lock battery: If you buy a smart lock for your home, you will need to monitor its battery level. They can last from six months to a couple of years, but eventually the battery will need replacing or recharging.
• Phone battery: If you plan to use your phone as your key, you will also need to ensure it doesn’t run out of battery before you arrive home.  
• Updates: They may require occasional firmware updates to fix bugs or security issues. 
• Security risk: Smart locks could pose a cybersecurity risk because they may be vulnerable to hacking. However, it's worth considering that mechanical locks can be picked. 
• Wi-fi connectivity: You will need to be connected to the internet to access some features, like remote unlocking. 
• Price: They are more expensive than traditional locks. You might spend £200 to £300 on a smart lock, while standard front door lock replacements typically cost between £90 and £170. 
• Home insurance: If it’s hacked or a password is stolen, it could affect your ability to claim on your home insurance. Be sure to check this with your provider. 

What happens to smart locks during a power cut? 

Smart locks are often battery-powered, so if there’s a power cut, the door will stay locked and the motor will still work. 

You will be able to enter the house using the keypad, fob, fingerprint scanner, or your phone, provided you are nearby with Bluetooth connectivity. 

If the power cut also affects your wi-fi, you may not be able to use other features like remote unlocking, access logs, and voice control. 

Since the lock is battery-operated, you'll need to ensure its battery doesn’t die. You should receive a notification in the app if it’s running low. 

Do smart locks void home insurance?

As long as it meets British Standards, installing a smart lock shouldn't void your home insurance, though there are a couple of caveats.

Dean Sobers, Which?'s insurance expert, says: 'The advice insurers give around smart locks is mixed, reflective of their relative newness and the fact they come in different shapes and sizes.

'Some will view it as an enhancement to your security arrangements – but only where combined with a robust mechanical locking mechanism that meets British Standards.'

'However, if it’s hacked or a password is stolen, this could affect your ability to claim. If you’re considering getting one fitted, or have one and are switching insurer, it’s worth contacting the insurer to explain the exact type of device to ensure it’s one they recognise and approve of.'

Find out which provider you should use in our guide to the best home insurance. 

How else can I make my home smart?

From robot vacuums that learn your floor layouts to smart TVs that recommend your evening's entertainment, almost every household device has a smart version designed to make your life a little easier.

Here are a few other ways to upgrade your home: 

• Smart speakers give you voice control for all your smart tech.
• Smart lights automate your lighting.
• Video doorbells let you know when someone is at the front door.
• Outside security cameras and smart security systems give you peace of mind when you’re away.
• Indoor security cameras reassure you that everything is okay inside your home.
• A smart thermostat gives you more control over the heating.