If you’re running Windows 10 in your Dublin office or across multiple sites, you’ve probably heard the deadline: October 14, 2025. That’s when Microsoft stops supporting Windows 10 entirely. No more security updates, no more patches, no more safety net.

We know what you’re thinking: “Another deadline? Another thing to manage?” It’s fair to feel that way. But here’s the honest truth — this one actually matters, and waiting until the last minute is going to cost you more money and headaches than planning ahead.

Why This Deadline Isn’t Hype

Once Windows 10 support ends, your devices become sitting ducks for cyber-attacks. Every new vulnerability discovered will have no official fix. For Irish businesses handling customer data or employee information, this creates a serious GDPR compliance risk. The Data Protection Commission won’t look kindly on organisations running unsupported systems — especially if a breach happens.

There’s also the practical stuff: software vendors will start dropping Windows 10 support, Microsoft 365 performance will degrade, and you’ll lose access to modern security features that competitors are already using.

What You Actually Need to Do

First, take stock. How many machines are you running? What hardware? This doesn’t require an IT degree — just a basic count of laptops, desktops, and any older machines still in use. Older hardware might struggle with Windows 11’s requirements (processor, RAM, storage), so knowing what you’ve got is step one.

Second, budget realistically. Windows 11 itself is free if you’re upgrading within the licence agreement. But some older machines might need upgrades — extra RAM, solid-state drives, or even replacement. A handful of machines might not be worth upgrading at all; sometimes retirement and replacement makes more sense. Costs vary, but Irish businesses typically budget €150–400 per device for a smooth transition including hardware upgrades and testing.

Third, test before you roll out. Don’t migrate everything on day one. Pick a department, run Windows 11 for a few weeks, see what breaks. Find out whether your line-of-business software works. Discover problems in a controlled way rather than during your busiest quarter.

The Hidden Benefit

Here’s something most people miss: migrating to Windows 11 is a chance to clean house. Old software, redundant licences, unused apps — they all get reviewed during the process. Many Irish businesses find they’re actually more organised and secure after migration than they were before.

A Practical Timeline

• Now (mid-2026): Audit your devices and software compatibility
• Late 2026: Start pilot migrations with one team
• Early 2027: Roll out to departments in phases
• September 2025 onwards: Final stragglers and problem-solving

The October 2025 deadline might seem far away, but IT migrations rarely go smoothly when rushed. Six months of planning beats six weeks of panic.

If you’d like someone to do that device audit for you — no charge, no obligation — we offer a free Windows 11 readiness assessment. We’ll tell you exactly what you’re working with and what the realistic costs and timeline look like for your business. Ring us on 01 234 5678 or email hello@castlecomputers.ie.