Why you shouldn’t leave the key in the lock at night
Leaving your keys in the door at night might seem harmless, but it can actually make your home less secure. Learn why you shouldn't leave your key in the lock, as well as lock safety, key management, and burglary prevention advice from Verisure's experts. Plus, we share practical home security tips to help you protect your home at night.
Many people believe that leaving the key in the lock at night adds security, as a way to "seal" the door before bed. But, while it may seem like a safe reflex to protect against intrusions, this habit can actually create hidden security risks.
In reality, leaving your key in the lock can make it easier for burglars to break in, prevent a quick escape during emergencies, and even damage your door's locking mechanism over time.
This guide from Verisure's home security experts explains why you shouldn't leave the key in the lock, how burglars can actually exploit this oversight, and what safer alternatives can help protect your home and family.
Why do people leave their keys in the lock?
If you lock up your apartment and leave the keys in the door at night, you wouldn't be the only one. It's an incredibly common key management habit that you, alongside many homeowners, may think is protecting your home at night. For one, it's convenient and, for two, it's reassuring.
Most people leave their keys in the lock for the following reasons:
- They worry about losing or misplacing their keys.
- They try to reduce the time spent looking for their keys in the morning.
- They believe leaving the keys in is part of lock safety, and prevents burglars from picking the lock.
- Keeping the keys in the door seems like a fast exit option during an emergency.
However, all of these well-meaning intentions can backfire. In fact, reputable locksmiths and police forces up and down the country consistently warn that leaving keys in the lock can leave your house or apartment open to greater risk.
Lift. Lock. Remove.
In fact, the Metropolitan Police have even come up with a mnemonic to help homeowners with modern, multi-locking and uPVC doors remember to take their keys out:
Lift. Lock. Remove. Lift up the door handle, lock the door, and take your keys out, before storing them somewhere safe for the night.
Why you shouldn't leave the key in the lock at night
You should never leave your keys in the door at night because it makes it easier for burglars to gain access to your property, increases fire safety risks in case of an emergency, and can damage or jam your door lock.
Burglars can unlock doors from outside
Skilled intruders use tools like rods, hooks, or even simple wires to manipulate the key through the cylinder of the lock, a method known as "letterbox fishing" - turning it from outside and quietly unlocking your door within seconds.
It increases fire and safety risks
A key left in the lock can jam or block the mechanism, making it harder to open the door quickly in an emergency. A blocked lock can also delay rescue teams from entering your property to help you to safety in time.
You could invalidate your insurance
If a burglar gains entry because your keys were left in an obvious place or within reach, your insurer may view it as negligence - potentially invalidating your home insurance claim.
You can damage or jam your lock
Over time, leaving a key in the lock can cause mechanical strain or misalignment inside the cylinder, increasing the chance of keys bending, snapping, or becoming stuck - and leading to costly repairs.
Remember: Lift. Lock. Remove.
Is it ever safe to leave keys in the lock?
Many people wonder is it safe to leave the key in the lock even if just for a short period, or while they're at home during the day. And the short answer is still no, not for external doors.
Even if you live in a quiet area or an apartment, burglars often target properties that show small signs of vulnerability. Keys visible through glass doors or reachable via letterboxes make your home an easy target.
For interior doors, it's generally less risky, but experts still advise against the habit. Instead, try the following home security tips when locking up:
- Keep keys on a dedicated hook inside a cupboard or hidden from view, a few metres from the door, to reduce temptation for opportunistic thieves.
- Make sure everyone in your household knows where the keys are stored, so they can be easily located in an emergency without compromising safety.
- Avoid leaving keys in a place that's visible from windows or letterboxes, as burglars can use tools to grab them in what's known as "letterbox fishing".
- Create a nightly lock-up routine, checking that all keys are safely stored away and doors and windows are secured before bed.
For added protection, consider investing in smart locks or door and window sensors from Verisure, for enhanced burglary prevention and peace of mind when protecting your home.
How do burglars exploit keys left in locks?
As we touched on above, leaving the key in the lock may be unwittingly lending a helping hand to burglars looking for an easy way in. Thieves can use the following quiet and clever methods to exploit keys left in locks:
Letterbox fishing
This involves inserting a long hook or rod through your letterbox and manoeuvring it to turn the key and open the door. Alternatively, thieves occasionally use a similar "fishing" tactic to grab keys from a nearby table or bowl using a rod, pulling them out through the letterbox and gaining access to the house from the outside.
Gaining access through glass panels
If your front door has a glass panel in it or decorative glass around the sides of the door, burglars can smash the glass, reach inside, and turn the key that's already in the lock to gain access to the house. If your keys are hidden away out of view, this method becomes much harder, if not impossible.
Lock manipulation
Professional thieves can insert thin tools into your lock to rotate the key from the outside. With the key acting as leverage, it's easier to bypass the lock entirely and open the door.
Distraction or impersonation
Some thieves will even use more sophisticated tactics to make the most of an exposed key. In some rare cases, burglars may pose as a delivery person or tradesperson to get close enough to a door to steal an exposed key. Verifying identities through a spyhole, using a doorbell camera, and not opening the door to unexpected callers reduces this risk.
Protecting your home at night without leaving keys in the door
Now you understand why you should never leave keys in the door at night, let's take a closer look at some burglary prevention tips for keeping your home secure.
Nighttime security habits
It's a good idea to get into the habit of checking that your key is not still in the lock before you go to bed every night. If you make this double-checking part of your nighttime security habits, you're much less likely to forget.
If you live with others, encourage them to do the same, and decide upon a safe place to put your key instead. The best part? Knowing your home is that bit more secure will help you sleep better at night, too.
Keep keys out of sight: what's the safest place to keep your keys at night?
When you do remove your keys from the lock, don't be tempted to throw them on a table near the door or place them on a windowsill.
These are not secure locations either, inviting quick thefts from opportunistic burglars chancing their luck with a glance into your property through a glass panel or window.
A drawer away from the door is the best place to store your keys, but you could also try hanging them on the inside of a cupboard door to hide them from view. Whatever you do, never leave a spare key under a mat or flower pot, as these are well-known hiding spots for burglars to look for.
Upgrade to a monitored alarm system
One of the most effective ways to protect your home and avoid the risks associated with leaving keys in the lock is to invest in Verisure's 24/7 monitored alarm system.
Unlike traditional home security, Verisure's system combines smart technology, remote access, and constant professional monitoring to ensure your property is protected day and night. You can manage and check your system easily through the Verisure mobile app, giving you full visibility and control wherever you are.
With a Verisure monitored alarm system, you can:
- Arm or disarm remotely using your smartphone.
- Receive instant alerts if a door or window is opened unexpectedly.
- Check system status in real time for peace of mind.
- Rely on 24/7 professional monitoring for a verified response in the event of an alarm.
At the heart of every Verisure system is its Alarm Receiving Centre (ARC), staffed around the clock by trained security professionals. If your alarm detects unusual activity, the ARC team immediately receives an alert, verifies the situation using sensor data, and, if a genuine threat is confirmed, contacts emergency services or a Verisure security guard on your behalf.
This direct link between your home and Verisure's monitoring centre means that any intrusion, tampering, or attempted break-in triggers a fast, coordinated response, keeping your home protected even when you're asleep or away.
By replacing physical keys and outdated security habits with a professionally monitored alarm system, you gain not only convenience but complete confidence that your home is always secure, watched over, and ready to respond instantly if danger arises.
How does remote monitoring work?
Once your Verisure monitored alarm system is active, every sensor in your home works seamlessly with Verisure's Alarm Receiving Centre (ARC), the heart of the system's protection.
When an alarm is triggered, such as a forced entry, door tampering, or unexpected movement, the alert is sent instantly to the ARC, where trained security professionals assess the situation in real time.
Using advanced sensor data (and, when available, audio or visual verification), the team determines whether the alert signals a genuine threat or a false alarm.
If a security breach is confirmed, emergency services or a Verisure guard are immediately dispatched to your property, ensuring a fast, coordinated response.
Call a professional installer like Verisure
When installing a Verisure monitored alarm system, it's essential to rely on professional installation for maximum protection. Verisure's certified experts ensure every component, from door and window sensors to cameras and control panels, is positioned and configured to meet the highest security standards.
This meticulous setup guarantees that your system is fully integrated, reliable, and ready to respond in any situation. It also ensures seamless connectivity with the Verisure mobile app, giving you full control and visibility over your home's safety.
Use letterbox guards and door chains
Lastly, investing in a letterbox guard is an easy way to improve the security of your home. It's designed to prevent anyone from reaching through to turn locks or hook keys out, like in the letterbox "fishing" procedures we covered above.
Getting a door chain or bar lock is another great piece of burglary prevention advice, since they add yet another level to your lock safety set-up - acting as a barrier between your home and potential intruders.
FAQs
Burglars usually check obvious hiding spots like under doormats, flower pots, and window ledges. So, even if you keep your keys out of sight, they may not necessarily be safe from experienced burglars who know the common hiding places.
Yes, typically authorities recommend using a secure, police-approved key safe rather than hiding keys outside. These provide controlled access and are far safer when installed correctly.
Instead of using a key safe, you can give a spare key to a trusted neighbour or family member, or switch to smart locks that remove the need for physical keys.
Home security you can rely on
By replacing outdated habits (like leaving keys in the lock) with modern technology, you take more control over your home's safety and enjoy the peace of mind that comes with it.
With Verisure's smart alarm systems, connected locks, and professional monitoring, you can eliminate the need for physical keys, deter break-ins, and respond quickly to emergencies 24/7.