Microsoft ended support for Windows 10 on 14 October 2025. The machines kept working. They stopped receiving security updates, unless somebody paid for them.
A year on, most small businesses fall into one of three groups. Some upgraded everything to Windows 11. Some bought Extended Security Updates for the machines they could not move. And some did nothing, because the computers still turned on and nothing looked different.
The third group is larger than you would expect, and October is when that choice gets more expensive.
What "end of support" means in practice
A Windows 10 machine outside the paid program receives no security fixes for anything discovered after October 2025. Every vulnerability found since then stays open on that machine for good.
That does not mean it gets compromised tomorrow. It means the protection that used to arrive every month has stopped, and the gap widens with each one that passes. For a machine that opens email attachments and browses the web every day, that is the wrong direction to be moving in.
It also shows up on paper. Cyber insurance applications increasingly ask whether you run unsupported operating systems. A Windows 10 machine outside the paid program is a yes to that question, and answering it incorrectly is a problem in its own right. More on that in what cyber insurance asks BC small businesses.
What Extended Security Updates cost
Extended Security Updates, usually shortened to ESU, is Microsoft's paid program for organisations that need more time. It is sold per device, one year at a time, and the price doubles each consecutive year, for a maximum of three years.
In Canadian dollars, that works out to roughly:
| Coverage year | Price per device (CAD) |
|---|---|
| Year one, from October 2025 | about $86 |
| Year two, from October 2026 | about $172 |
| Year three, from October 2027 | about $345 |
The years are cumulative. Microsoft states that if you enrol in year two, you pay for year one as well. A machine joining this October costs about $258 per device for coverage through to October 2027, even though the first year has already passed.
The machine also has to be running Windows 10 version 22H2 to be eligible, and ESU includes security updates only. No new features, no general fixes, and no technical support for Windows itself. The exact price depends on where you buy it and the exchange rate on the day, so confirm it with whoever handles your Microsoft licensing before you budget.
There is one route where ESU is included at no extra cost: Windows 10 machines connecting to Windows 365 Cloud PCs, with an active Windows 365 subscription. For most small offices that is a bigger change than the problem it solves, but it is worth knowing it exists.
Deciding machine by machine
The right answer is rarely the same for every computer in the office, so look at each one.
It can run Windows 11. Upgrade it. The upgrade is free on eligible hardware, and it ends the problem rather than renting a year's reprieve. Check eligibility properly before you promise anyone a date, because older processors and missing security chips are the usual reasons a machine does not qualify.
It cannot run Windows 11 and it is a normal office computer. Replace it. A laptop that cannot run Windows 11 is almost always old enough that it would be due for replacement within a year or two anyway, and roughly $258 in ESU buys that machine one more year on borrowed time. Put the money towards its replacement instead.
It runs something that cannot move. Every office has one: the computer attached to a plotter, a piece of lab or diagnostic equipment, or software the vendor never updated. ESU was designed for exactly this machine. Pay for it, and put the machine on its own segment of the network so it cannot reach, or be reached from, everything else.
It is the one nobody remembers. The old desktop in the back room that still logs into email, or the reception PC that has not been touched in years. Find these first. Machines that nobody thinks about are the ones that never get upgraded.
What to do this month
- List every Windows 10 machine. Including laptops that are rarely in the office and the computer in the back room.
- Sort each one into the four groups above.
- Upgrade what can be upgraded. It is free, and it is usually an afternoon per machine.
- Order replacements for the machines that cannot, and decide whether any of them justify ESU in the meantime.
- Buy ESU only for the machines that genuinely have to stay, and isolate them.
Doing nothing remains an option. It is just the only option that gets riskier every month without costing anything upfront, which is exactly why it is so common.
Operating system upgrades, hardware planning and patching are part of every managed IT plan we run. We recommend hardware, you buy it, and we do not take a margin on it.
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