Windows 10 will reach end of support on 14th October 2025. By this date, businesses will need to sign up for Extended Security Updates (ESU) options or risk using an increasingly vulnerable operating system.
The Microsoft ESU programme is expected to run for 3 years through to 2028, but if other Microsoft pricing models are followed, the cost per year is likely to escalate over this period. Nexthink is warning that the cost of custom Windows 10 support could reach upwards of $7.3bn, based on market share data and business usage estimates.
Of the 1.4 billion devices powered by Windows, Nexthink estimates that approximately 30% are in use by commercial or public sector organizations, equating to around 420 million enterprise Windows devices. The latest market share data shows that Windows 10 still has a 43% share, which is equivalent to roughly 181 million devices.
According to Nexthink’s analysis of customer endpoints, there has been a 33% decrease in Windows 10 devices between 19th May and 1st August. Assuming a further 33% reduction by 14th October, that would leave around 121 million Windows 10 PCs. At $61 per device for the first year of custom support, organizations could collectively be facing a bill of just over $7.3bn.
Nexthink’s analysis of the digital experience across Windows 10 and Windows 11 shows that Windows 11 devices are currently experiencing a higher level of instability, with more frequent system crashes (1.2% vs 0.6% for Windows 10) and hard resets (9.9% vs 8.5% for Windows 10). While not unexpected in the early years of a new operating system, the findings highlight how factors such as hardware compatibility, drivers, and system configuration can impact the employee experience during an OS migration. These risks can be anticipated and mitigated with tailored library packs, which give IT teams ready-to-use insights and guidance to smooth the transition.
Nexthink says that organizations must take a proactive, data-led approach to migration planning, ensuring they understand both the technical requirements and the potential impact on the employee experience. To do this, organizations should:
- Pinpoint remaining Windows 10 devices and assess hardware readiness for Windows 11.
- Plan for post-deadline risks, as unsupported devices face greater exposure to malware, phishing, and ransomware.
- Check application compatibility to prevent software issues or loss of support.
- Factor in device performance, as older hardware may slow productivity and limit upgrades.
- Consider IT resource impact, as unsupported OS devices may require more IT support.
- Reduce friction across teams by avoiding inconsistent experiences between Windows 10 and Windows 11 users.
Methodology
The full workings for the Nexthink calculation are as follows:
- There are 1.4 billion devices powered by Windows, of which Nexthink estimates that around 30% are in use by commercial or public sector organizations.
- This leaves 420 million enterprise Windows devices. If 43% of these are Windows 10 devices, that leaves 180,600,000 Windows 10 enterprise devices.
- Assuming a 33% reduction in the 74 days from 1st August to 14th October (59,598,000), this will leave 121,002,000 devices due to be upgraded.
- At $61 per device, this makes the cost of Windows 10 custom support worldwide $7,381,122,000.






