Independent comparisons. We may earn from shop links. More info

Smart door lock buying guide

Updated: 16 October 2026

You are at a UK front door with a tape measure, and amazon.co.uk is using one name for five different products. A timber nightlatch, a handle you lift to lock, a euro cylinder you keep, a new cylinder in the box, and a fingerprint lever near £40 will not operate one another. This smart door lock buying guide is the step before the shortlist on our [smart door lock](/hub/electronic-surveillance/smart-door-lock) comparison. Prices and review counts are the amazon.co.uk figures we recorded on 15 October 2026. The Products Compared editorial team did not laboratory-test these locks. A qualifying purchase can earn us a commission at no extra cost to you.

You are at a UK front door with a tape measure, and amazon.co.uk is using one name for five different products.

Our top picks

Nuki Nuki Smart Lock Ultra, euro cylinder included

Best overall

Nuki Nuki Smart Lock Ultra, euro cylinder included
9.2/10about £309
View offer
TEKXDD TEKXDD fingerprint handle, matte black

Best value

TEKXDD TEKXDD fingerprint handle, matte black
8.6/10about £39.99
View offer
Yale Yale Keyless Connected, black, 60 mm nightlatch

Alternative

Yale Yale Keyless Connected, black, 60 mm nightlatch
8.4/10about £68
View offer
On this page
  1. 1.Four locks that share one search
  2. 2.What to measure before you pay
  3. 3.What the amazon.co.uk boxes in this set include
  4. 4.When the format choice is really an insurance choice

Four locks that share one search

Name the mechanism on the door, then open only that group of listings. A timber door with a rim nightlatch takes a keypad around a 60 mm backset. The chrome Yale Keyless Connected is £70.32, and the latch is left out of the box. The black Yale Keyless Connected is £68.00, and the title includes a 60 mm nightlatch. A door you lock by lifting the handle is a different purchase. The Yale Conexis L2 is £188.98, stated for PVC and composite doors of 44–70 mm, with the Wi-Fi bridge included. The Nuki Pro, at a raw £229.00, turns the cylinder you keep. The Nuki Ultra, at £309.00, supplies a universal cylinder and new keys. If you are choosing between the Conexis and a Nuki, use Yale Conexis vs Nuki after you have measured.

What to measure before you pay

Measure the leaf at lock height, in millimetres. The Conexis listing states 44–70 mm for PVC and composite doors. The TEKXDD states 35–55 mm. Backset, for a nightlatch, runs from the face of the latch to the centre of the keyhole or spindle. Both Keyless units are built around 60 mm. For a euro cylinder, measure each side from the fixing screw, inside and outside separately. The Pro keeps your cylinder, so the check is whether a key still works from both sides with the inside key left in. If the key only turns when you lean on the door, follow the pre-fit test on how to fit a smart door lock.
Nuki Nuki Smart Lock Ultra, euro cylinder included

Testsieger

Nuki Nuki Smart Lock Ultra, euro cylinder included
9.2/10about £309
View offer

What the amazon.co.uk boxes in this set include

Read the included line. On the chrome Keyless the nightlatch has to be on the door already, and the Access Module is absent from both colours. This Conexis includes the lock, the Wi-Fi Connect bridge, a key tag, a key card, and a fixing pack. The Pro’s included line is the lock only, with built-in Wi-Fi and no cylinder. The Ultra includes the lock, a universal cylinder, a mounting plate, a charging cable, and a black cover.

When the format choice is really an insurance choice

None of the eleven amazon.co.uk listings in this comparison prints BS 3621 or TS 007 on the bullets we captured. Allianz’s public guidance is that many insurers still expect a traditional BS 3621 lock alongside a smart lock, and that you tell them before you fit one. The Pro leaves the existing cylinder in the door. The Ultra, the Conexis, the Ruveno, and a fingerprint lever used as the only lock on a final exit change the hardware a schedule may describe. Read the difference between a mortice mark and a cylinder mark on smart lock home insurance.

Common questions

Is my door a nightlatch or a euro cylinder?
Look at the edge of the door. A nightlatch is a rim lock on the inside face of many older timber doors, and the Keyless keypads here expect a 60 mm backset. A euro cylinder is the oval profile in the edge, held by one screw, on a lot of uPVC, composite, and timber doors. If you lock by lifting the handle until the hooks throw, you are in the lift-to-lock group, with the Conexis or the Ruveno, rather than either of those two.
Do I still lift the handle after a smart lock is fitted?
On a lift-to-lock door, yes. Which? and Yale’s Conexis guidance both describe locking as lifting the handle until the mechanism has thrown. The app, a tag, or a card is how you unlock. A Nuki Pro turns the cylinder instead, so the handle routine stays whatever the multipoint already uses. A fingerprint lever locks like an ordinary lever.
Will a £40 fingerprint handle fit a uPVC front door?
Only when that door’s thickness and lock case match the listing, which these handles rarely do on a UK multipoint final exit. The TEKXDD states 35–55 mm. Many uPVC leaves are thicker, and the hooks of a multipoint are a different mechanism from the latch in a fingerprint lever. Use one on a bedroom or office door inside the stated band.
What thickness do I measure?
Measure the full door leaf at lock height, in millimetres. For a euro cylinder, also measure the inside length and the outside length from the fixing screw, because the two sides often differ. For a nightlatch, measure the backset and compare it with 60 mm before you order a Keyless unit.
Does the box include the latch, the bridge, or the cylinder?
It depends on the ASIN. The chrome Keyless omits the nightlatch. The black Keyless title includes a 60 mm nightlatch. Neither includes the Access Module. This Conexis includes the Wi-Fi bridge. The Nuki Pro is the lock only. The Nuki Ultra includes a universal cylinder. The TEKXDD includes handles and instructions, and the four AAA batteries are extra.
Should I read the insurance page before I choose a cylinder replacement?
Yes, when the lock you are changing is the one named in your home policy. The Ultra replaces the euro cylinder. The Pro clamps over a cylinder you keep. Both are worth an email to the insurer before you pay.

Related pages

Best smart door locks

Smart door lock

Smart lock home insurance: ask before a cylinder swap

How to fit a smart door lock: measure and then fit

Yale Conexis vs Nuki: handle, Pro, or new cylinder

Sources

Public UK sources for the standards, insurance wording, and product-security rules, last checked on 15.10.2026. Prices and star ratings are the amazon.co.uk figures captured that day.

  1. GOV.UK: Regulations for consumer connectable product security (retrieved 15.10.2026)
  2. Product Security and Telecommunications Infrastructure (Security Requirements) Regulations 2023 (retrieved 15.10.2026)
  3. Allianz UK: Stay insured with the right house locks (retrieved 15.10.2026)
  4. MoneySuperMarket: What locks do I need for home insurance? (retrieved 15.10.2026)
  5. Secured by Design: Locks and associated hardware (retrieved 15.10.2026)
  6. Yale Home: Compatible with Conexis (retrieved 15.10.2026)
  7. Nuki Help: What is the emergency function? (retrieved 15.10.2026)
  8. Which?: Do I need a smart door lock? (retrieved 15.10.2026)