Planning a Windows 11 Migration Before the ESU Deadline: A Rollout Guide for UK Businesses

The clock is running down. Windows 10 stopped getting free support in October 2025, and the paid safety net that replaced it, Extended Security Updates, runs out in October 2026. After that date, Microsoft stops shipping security patches for Windows 10 completely. Any flaw found later stays open on those machines for good.

So this is the last realistic planning window. If you leave the move until September, you will be doing it in a rush, and rushed IT projects are the ones that lose data and break the apps your team needs to do their jobs.

Buying the new hardware is the easy part. Our sister site covers that side in its Windows 10 business hardware upgrade guide, which walks through the hardware check and what to look for in a new machine. This guide deals with the harder bit: how you actually move a whole business across to Windows 11 without grinding work to a halt.

Why a migration is a project, not a button

Upgrading one home laptop is a click. Moving thirty, or three hundred, business machines is a different animal.

You have got line-of-business software that has to keep working. You have got user files, profiles, saved passwords and mapped drives that people expect to find exactly where they left them. You have got staff who cannot afford to lose a morning to a machine that will not log in. And you have got a security baseline that needs to be right on day one, not bolted on later.

Get the planning right and most of your team will barely notice the switch. Get it wrong and you will spend weeks firefighting. The difference is almost always in the preparation, not the install.

Start with an honest audit

You cannot plan a move if you do not know what you are moving. Before anything else, build a simple inventory of every device in the business. For each one, record its age, its specification, and whether it passes the Windows 11 hardware requirements.

That last check is where most older business PCs fall down. Windows 11 needs a security chip called TPM 2.0, Secure Boot, a supported processor and a sensible amount of memory and storage. The processor rule catches the most machines. As a rough guide, anything more than six or seven years old is likely to fail.

Sort your machines into three piles:

• Ready to migrate. Passes the check, good enough spec, stays in service.
• Upgrade first, then migrate. Passes the check but feels slow. A memory top-up or a solid state drive brings it back to life for a fraction of the price of a new machine.
• Replace. Too old to qualify, or too slow to be worth keeping.

For the machines in that middle pile, an in-place upgrade often makes more sense than a replacement, especially with hardware prices climbing this year. Our computer repairs team handles memory and drive upgrades in bulk, so a batch of tired but capable PCs can go back to staff feeling quick again rather than heading to the skip.

Test your software before you touch a single machine

This is the step people skip, and it is the one that causes the most pain.

Most mainstream software runs fine on Windows 11. The trouble tends to sit with the odd, business-critical bits: an old accounting package, a bespoke database, a piece of industry software that has not been updated in years, or a device driver for a scanner or a label printer that the manufacturer stopped supporting.

Make a list of every application the business relies on. Then check each one for Windows 11 compatibility. For the important ones, do not just take the vendor’s word for it. Test them on a real Windows 11 machine before you roll anything out. Finding out that your booking system will not run is a headache in a test lab. It is a disaster on migration morning with forty people waiting to work.

If a critical app genuinely will not move, you have got options: a newer version, a supported alternative, or in some cases running the old app in a controlled way while you find a proper replacement. The point is to know now, not later.

Sort out your data and user profiles

Nobody thanks you for a shiny new operating system if their files have vanished.

Before any machine gets touched, make sure everything important is backed up and, ideally, synced to the cloud. Documents, desktop files, browser bookmarks, saved passwords, email signatures, mapped network drives, printer connections. These are the small things that, when missing, make a user feel like the whole move was a mistake.

A clean, well-planned migration moves all of that across so the machine feels familiar the moment someone logs in. If your business runs on Microsoft 365, a lot of this can travel with the user account automatically, which makes the whole job smoother. Getting that set up properly is exactly the sort of thing managed IT support is for, so the migration becomes a planned service rather than a scramble.

Roll it out in waves, not all at once

Resist the urge to do everything on one big weekend. It rarely goes to plan, and if something breaks you have broken it for everyone.

A far safer approach is to migrate in batches. Start with a small pilot group, ideally people who are comfortable with a bit of change and will tell you honestly what felt off. Iron out the wrinkles. Then move the next group, and the next.

Waves give you three things: you learn and improve as you go, you never have the whole company down at once, and you can schedule each batch around the team’s actual workload rather than forcing a single high-pressure cutover. Payroll week is a bad time to migrate the finance team. You know your business rhythm, so use it.

Do not forget the network underneath

A fleet of new machines will happily expose a tired network. If your Wi-Fi already struggles at busy times, or your switches are past their best, adding faster devices will not fix that, it will just make the bottleneck more obvious.

A migration is a natural moment to check the plumbing. If the network needs attention, it is far cheaper to sort it as part of the same project than to discover the problem afterwards. Our network support team can assess switching, wireless and firewalls alongside the rollout so everything lands together.

Lock in the security on day one

Here is the part that turns a migration from a chore into a genuine upgrade. Windows 11 has stronger security built in, but you only get the benefit if it is configured properly.

While you are touching every machine anyway, set the security baseline right:

• Turn on multi-factor authentication across staff accounts. This is now expected under the updated Cyber Essentials requirements, and it is one of the single most effective things you can do to stop an account being hijacked.
• Set up proper device management so machines can be secured, updated and, if lost or stolen, wiped remotely.
• Remove local administrator rights from standard users.
• Make sure disk encryption is switched on.

Doing this during the migration is efficient. Trying to retrofit it across a fleet six months later is a much bigger job. The National Cyber Security Centre’s device security guidance is a solid reference for getting the baseline right.

For businesses in regulated sectors, this matters even more. Firms in financial services and organisations in healthcare both need to show that their systems are supported and secure, and running an unsupported operating system is the kind of thing that shows up badly in an audit or a cyber insurance renewal. Schools face the same expectation through the Department for Education’s standards, which our IT support for schools and education team works to directly.

What about machines you have to keep on Windows 10 for now?

Sometimes there is a machine you genuinely cannot move yet. A PC tied to a specific piece of equipment, or one running software with no Windows 11 version available.

For those, paid ESU buys you a bit of breathing room, but treat it as a short bridge and nothing more. The cost rises each year, and an unsupported machine on your network is a risk to everything else connected to it. If it is a piece of ageing hardware you are keeping running out of necessity, a third party IT hardware maintenance contract can keep it covered and supported while you work towards a permanent fix.

A simple plan you can actually follow

Pulling it all together, here is the shape of a sensible migration:

1. Build your device inventory and run the Windows 11 check on every machine.

2. Sort machines into migrate, upgrade-then-migrate, and replace.

3. List your business software and test the critical apps on Windows 11.

4. Back up and sync all user data and profiles.

5. Run a small pilot group first and fix what breaks.

6. Roll out the rest in scheduled waves.

7. Check the network can handle it.

8. Set the security baseline on every machine as you go.

9. Deal with any stubborn Windows 10 holdouts as a separate, tracked exception.

None of this is complicated on its own. The value is in doing it in the right order, with enough time, before the deadline forces your hand.

Where we come in

Most businesses do not have the spare hands to run a fleet-wide migration on top of the day job. That is the common reason it gets left too late.

Euroland IT Services plans and runs Windows 11 migrations for businesses across London and the wider UK. We audit the estate, test the software, upgrade the machines worth keeping, replace the ones that are not, move everyone across in controlled waves, and set the security up properly at the same time. You get a plan, a timeline, and a team that has done this before.

The deadline is fixed. The amount of stress involved is not. Move now, while there is time to do it calmly.

Book a free Windows 11 migration readiness assessment. We will map which machines migrate, which get upgraded, which get replaced, and give you a clear rollout plan. Call us or request a callback.

Frequently Asked Questions

Q1: When exactly does Windows 10 support end?

A: Standard support ended in October 2025. Paid Extended Security Updates carry on until October 2026, after which Windows 10 gets no more security patches at all. Any vulnerability found after that stays unpatched.

Q2 :Can my current PCs run Windows 11?

A: Some can, some cannot. Windows 11 needs TPM 2.0, Secure Boot, a supported processor and minimum memory and storage. Machines roughly six or seven years old and newer often qualify. The best way to know is to check every device rather than guess.

Q3 :Will we lose files or settings during the migration?

A: Not if it is planned properly. A good migration backs up and moves documents, profiles, bookmarks, saved passwords, printers and drive mappings, so the machine feels familiar as soon as the user logs in. The risk comes from rushing without a backup, not from the upgrade itself.

Q4 :How long does a business migration take?

A: It depends on the number of machines and how much software testing is needed. Rolling out in waves spreads it over a few weeks, which is deliberately slower than a single cutover but far less disruptive and much safer.

Q5 :Is it cheaper to upgrade old PCs or replace them?

A: For a machine that passes the Windows 11 check but feels slow, a memory or drive upgrade is usually far cheaper than a new device and adds a few good years. For machines that fail the check or are very old, replacement is the better long-term value. A mix of both is normal.

Q6 :What if a critical application will not run on Windows 11?

A: Test for this early. If a key app genuinely will not move, the answer might be a newer version, a supported alternative, or a controlled workaround while you find a replacement. The important thing is discovering it in testing, not on rollout day.

Q7 :Do we really need multi-factor authentication?

A: Yes. It is one of the most effective defences against account takeover, and it is now expected under the updated Cyber Essentials requirements. A migration is the ideal moment to turn it on across the business.