It’s a question we’re often asked: should you switch your computer off at the end of every working day, or is it better to leave it running?
From an environmental and energy-saving point of view, the official answer is fairly straightforward. If you're not using your computer, switching it off reduces unnecessary electricity consumption. Across an office with dozens of PCs, those small savings can certainly add up over the course of a year.
However, there is another side to the story, particularly when it comes to IT maintenance and cyber security.
Night-time is often maintenance time
For many businesses, evenings and overnight periods are when IT systems carry out important maintenance.
This can include:
Windows security updates Microsoft 365 and application updates Antivirus and endpoint security updates Driver and firmware updates Vulnerability patches Automated maintenance tasks Backup and monitoring processes Remote IT maintenance
These jobs are deliberately scheduled outside normal working hours so they don't interrupt people while they're trying to work.
The problem is simple: if your PC is switched off, many of these tasks can't take place.
The computer will normally attempt to catch up with outstanding updates the next time it is switched on, but this can mean updates installing during the working day. We've all experienced the computer that decides it needs to restart just as we're about to join a Teams meeting!
More importantly, continually postponing updates can potentially leave a computer without the latest security fixes for longer than necessary.
So, should I leave my PC switched on every night?
Not necessarily.
For most office users, a sensible compromise is to switch computers off when they're not required, but leave them powered on overnight once or twice a week.
For example, your business might ask employees to leave their PCs switched on every Tuesday and Thursday evening. This gives IT systems a regular opportunity to install updates, perform maintenance and complete any other scheduled tasks.
It's important that the computer is actually left powered on and connected to the network. Depending on how your IT systems are configured, putting a laptop into sleep mode or closing its lid may prevent some maintenance tasks from running.
What about laptops?
Laptops introduce another consideration: power.
If you're leaving a laptop switched on overnight for maintenance, it's generally worth connecting it to its charger and leaving it connected to Wi-Fi or the company network.
If the battery runs flat or the laptop enters a deep sleep state, those overnight maintenance tasks may not complete.
Security updates are particularly important
Keeping computers updated is one of the simplest but most important parts of maintaining good cyber security.
Software vulnerabilities are discovered regularly, and manufacturers such as Microsoft release security updates to address them. The longer an important update remains outstanding, the longer the computer could potentially remain exposed to a known vulnerability.
For businesses working towards standards such as Cyber Essentials, keeping operating systems and applications properly supported and patched is also an important part of maintaining a secure IT environment.
What's the best approach?
Our advice is to find a sensible balance between energy efficiency and IT security.
Switch your computer off when it isn't needed, but consider leaving it switched on overnight for one or two nights each week so that updates and scheduled maintenance have an opportunity to complete.
Your IT provider may have specific maintenance windows in place, so if you're unsure, it's worth asking which nights your computers should be left running.
And, of course, if your IT team specifically asks you to leave your PC switched on tonight, there is usually a good reason!
Hope that helps 👍