If you live in Germany, France, Italy, Spain or most of continental Europe, your front door almost certainly uses a Euro profile cylinder — and that single fact shapes which smart lock you can install. Choosing a smart lock for Euro cylinder doors is straightforward once you understand the cylinder, how to measure it, and which retrofit options exist. This complete European guide walks you through buying and installing a Euro cylinder smart lock so your upgrade fits perfectly the first time.
What is a Euro profile cylinder?
The Euro profile (or “Euro”) cylinder is the standardised lock cylinder used across most of Europe. It has a distinctive shape — a round section with a cam and a flat “bull‑nose” — and comes in single, double and thumbturn variants. Because it is a standard, a smart lock for Euro cylinder doors can often replace or motorise the existing cylinder cleanly, which is why retrofit upgrades are so popular in European apartments and houses.
How to measure your Euro cylinder
Correct measurement is the whole game. A Euro cylinder length is given as two numbers — the distance from the central fixing screw to each end (for example 35/35 or 30/40). To measure:
- Open the door and locate the central fixing screw on the door edge.
- Measure from the screw to the outside face, then from the screw to the inside face.
- Record both numbers (e.g. 35/35 mm) and note whether it is single, double or thumbturn.
Getting this right ensures your smart lock for Euro cylinder installation sits flush and secure — a cylinder that protrudes too far is both unsightly and a security risk.
Retrofit options for a Euro cylinder smart lock
1. Cylinder‑replacement smart locks
These swap your existing Euro cylinder for a motorised smart cylinder. Clean, often keeps the same door furniture, and is popular for a discreet upgrade.
2. Motorised add‑on (thumbturn) units
These fit over the inside thumbturn and turn it electronically, leaving the outside untouched — ideal for renters because installation is reversible and the original key still works.
3. Full smart lock bodies
Where the door allows, a complete smart lock body brings fingerprint, face, PIN and card access alongside the Euro cylinder mechanism for the richest keyless experience.
Installation: what to check
- Cylinder length and type (single/double/thumbturn) — measured as above.
- Door thickness and material.
- Handing and multipoint mechanism if fitted.
- Whether you rent — choose a reversible add‑on if you may need to restore the original.
- Mechanical key backup and emergency power for peace of mind.
Many Euro cylinder smart locks are DIY‑friendly, but for multipoint or metal doors, professional fitting is wise. Our broader door compatibility guide explains the measurements that matter.
Keyless entry for European front doors
Once fitted, a smart lock for Euro cylinder doors brings the same benefits European buyers want: fingerprint or PIN entry, app control, temporary codes for guests and, on connected models, remote access. Pair that with strong, on‑device privacy and you have a modern front door that is both convenient and secure. For the wider European picture, see our best smart lock Europe guide.
Where Covlor fits in
Covlor® is a manufacturer‑led brand that engineers and tests its Smart Door Locks in‑house, an approach set out in why Covlor focuses on manufacturing quality. Its locks — the CR L45, CR L51, CR L88 and CR L99 — combine fingerprint, face recognition, PIN, RFID/NFC card and app access with a mechanical key backup and USB‑C emergency power. For European homeowners choosing a smart lock for Euro cylinder doors, that engineered foundation, plus a 2‑year warranty and a verifiable digital warranty, is exactly what protects a daily‑use security device. Browse the range in the Covlor store.
Frequently asked questions
How do I choose a smart lock for Euro cylinder doors?
Measure your Euro cylinder (e.g. 35/35 mm), note whether it is single, double or thumbturn, confirm door thickness and any multipoint mechanism, then pick a cylinder‑replacement, thumbturn add‑on or full smart lock body to match.
Can renters install a Euro cylinder smart lock?
Yes — a motorised thumbturn add‑on fits over the inside only, is reversible and keeps the original key working, making it ideal for rentals. Always check with your landlord first.
Is a Euro cylinder smart lock secure?
A quality one is, especially with anti‑snap cylinder protection, encrypted communication and a mechanical key backup. Choose an engineered brand and a correctly measured, flush‑fitting cylinder.
Find a smart lock that fits your door in the Covlor Smart Door Lock store, and read next about smart lock privacy in 2026.
