Windows 10 End of Life: What UK Businesses Must Do Now

On 14 October 2025, Microsoft officially ended support for Windows 10. No more security patches. No more bug fixes. No more updates of any kind. For the millions of UK businesses still running Windows 10 on at least some of their devices, that date marked the beginning of a growing security and compliance problem that will not go away on its own.

Six months on, many organisations have upgraded. Many have not. If your business falls into the second group, this guide explains exactly what end of life means in practice, what the risks are, and what your options are right now.

What End of Support Actually Means

Microsoft operates a fixed lifecycle for each version of Windows. During the support period, Microsoft releases regular security patches, bug fixes, and occasional feature updates. When a product reaches end of life, all of that stops.

Windows 10 end of support means:

• No more security patches - Any vulnerabilities discovered after 14 October 2025 will not be fixed
• No Microsoft support - You cannot raise support tickets with Microsoft for Windows 10 issues
• No compliance certifications - Microsoft will no longer certify Windows 10 against security standards
• Reduced software compatibility - Third-party vendors are progressively dropping Windows 10 support from their products

The operating system does not stop working on that date. Your machines will continue to boot and run applications just as before. What changes is that any security vulnerability found from that point on will remain permanently unpatched, making those machines an increasingly attractive target for attackers.

The Real Risk: What Happens to Unpatched Systems

To understand why this matters, consider what happened to businesses still running Windows XP when it reached end of life in 2014. In 2017, the WannaCry ransomware attack exploited a vulnerability in older Windows systems and caused an estimated £92 million in damage to the NHS alone. The vulnerability had been patched for supported systems months earlier. XP machines had no protection.

Windows 10 will follow the same trajectory. Attackers actively catalogue end-of-life systems and develop exploits specifically targeting them, knowing that the vulnerabilities will never be fixed. Your unpatched Windows 10 machines become more dangerous every month, not less.

Compliance and Regulatory Exposure

Beyond the technical risk, running end-of-life software creates regulatory exposure that many businesses overlook until it is too late.

Under UK GDPR, organisations are required to implement appropriate technical and organisational measures to protect personal data. Running operating systems that no longer receive security updates is increasingly difficult to defend as an appropriate measure. In the event of a data breach on a Windows 10 machine, the ICO is likely to view the continued use of unsupported software as an aggravating factor.

Businesses with Cyber Essentials or Cyber Essentials Plus certification should also be aware that running unsupported operating systems will cause them to fail recertification. The scheme explicitly requires that all devices run software that is still receiving security updates.

Software and Hardware Vendor Support

Microsoft is not the only vendor withdrawing support. Browser vendors, security software providers, and line-of-business application developers are all progressively dropping Windows 10 compatibility from their products. You may find that critical software stops receiving updates, or that new versions simply refuse to install on Windows 10 machines.

How Many UK Businesses Are Still Affected?

The scale of the problem is significant. Industry data suggests that at the point Windows 10 reached end of life, it still accounted for more than a third of Windows devices in active use globally. In the UK small business market, adoption of Windows 11 has been slower than Microsoft anticipated, partly due to hardware compatibility requirements that ruled out devices purchased before 2019.

Many businesses are running mixed estates - some machines on Windows 11, others still on Windows 10. This creates uneven risk across the organisation. An attacker who compromises a Windows 10 machine can use it as a foothold to move laterally through your network, even if your other devices are fully up to date.

Your Options

There are three realistic paths forward for businesses still running Windows 10.

Option 1: Upgrade Eligible Devices to Windows 11

If your hardware meets Windows 11 requirements, upgrading is straightforward and free. Windows 11 requires:

• A 64-bit processor running at 1GHz or faster with at least 2 cores
• 4GB RAM minimum (8GB recommended for business use)
• 64GB of storage or more
• TPM 2.0 (Trusted Platform Module) - the requirement that catches most older machines
• UEFI firmware with Secure Boot capable
• A DirectX 12 compatible graphics card

The TPM 2.0 requirement is the most common sticking point. Devices manufactured before 2017 or 2018 frequently lack TPM 2.0 hardware. Some machines have TPM 2.0 physically present but disabled in BIOS, which means it can be enabled without replacing any hardware.

Before assuming a device cannot be upgraded, have your IT team or MSP audit the hardware. Many devices that appear incompatible can be upgraded after a BIOS change.

Option 2: Replace Ineligible Hardware

For machines that genuinely cannot run Windows 11, replacement is the appropriate solution. This is not just about the operating system - hardware that cannot meet Windows 11 requirements is typically five to eight years old, and will be approaching end of life from a reliability and performance standpoint regardless.

When budgeting for hardware replacement, consider the full cost of running ageing equipment: increased support time, reduced staff productivity, higher failure rates, and the cost of emergency replacement when devices fail unexpectedly. Proactive replacement is almost always cheaper than reactive crisis management.

Option 3: Extended Security Updates (ESU) - A Short-Term Bridge

Microsoft offers Extended Security Updates for Windows 10, available for purchase on a per-device basis. ESU provides continued security patches for up to three years beyond end of life - through to October 2028 - but covers security patches only, not feature updates or technical support.

ESU is expensive relative to upgrading hardware, and it is explicitly designed as a bridge, not a long-term solution. It is most appropriate for specialist devices running software that is not yet compatible with Windows 11, where upgrading the hardware would require significant requalification of mission-critical applications.

For most small businesses, ESU is not the right answer. The cost typically outweighs the benefit compared to simply replacing the hardware.

How to Plan a Windows 11 Migration

A structured approach to migration avoids the disruption that comes from rushing the process.

Step 1 - Audit Your Estate

The first step is knowing exactly what you have. Run a hardware inventory across all devices to identify which are already on Windows 11, which can be upgraded, and which need to be replaced. A good RMM (Remote Monitoring and Management) tool can generate this report automatically across your entire fleet in minutes.

Step 2 - Check Application Compatibility

Before upgrading or replacing any device, verify that your business-critical applications run correctly on Windows 11. Most major software vendors have supported Windows 11 for some time now, but bespoke or legacy applications may need attention. Test in a controlled environment before rolling out widely.

Step 3 - Prioritise by Risk

If you cannot migrate everything at once, prioritise by risk. Devices handling sensitive data, customer information, or financial records should be upgraded first. Devices used exclusively for low-risk tasks can wait, provided they are isolated from your core network where possible.

Step 4 - Migrate in Waves

Avoid migrating your entire business simultaneously. A phased approach - one department or team at a time - allows you to identify and resolve issues before they affect the whole organisation. IT-MSP typically recommends three to four waves depending on business size.

Step 5 - Train Your Team

Windows 11 has a different interface from Windows 10. The Start menu has moved, settings are reorganised, and some familiar features work differently. A brief familiarisation session before migration reduces helpdesk calls and productivity loss in the days following the upgrade.

How IT-MSP Can Help

We have been supporting London businesses through the Windows 10 to Windows 11 transition since well before end of life arrived. Our managed migration service covers everything:

• Full hardware audit - We assess every device on your network and categorise it for upgrade, BIOS fix, or replacement
• Application compatibility testing - We validate your critical software against Windows 11 before a single production machine is touched
• Hardware procurement - For devices that need replacing, we source business-grade hardware at competitive prices and pre-configure it before delivery
• Managed rollout - We handle the upgrade process in waves, minimising disruption to your operations
• Post-migration support - Our helpdesk team is on hand to resolve any issues that arise after migration

If your business still has Windows 10 devices in active use, the time to act is now. Each month of delay increases your exposure and narrows your options. Contact our team for a free Windows 10 assessment and we will tell you exactly where you stand and what it will take to get fully up to date.