The top 5 IT security threats UK businesses face in 2026
Every year, we survey the security incidents our clients deal with and the threats we see in the wild. The picture for 2026 is more challenging than it's ever been — but the threats themselves are not exotic. They're the same five patterns, getting smarter and more automated each year. Here's what to watch out for, and what you can realistically do about each one.
The state of play
Before we get into the threats themselves, one important context point: small and mid-sized businesses are now the primary target for cybercrime. Not because attackers prefer you — but because you're easier to breach than a bank, and you can still pay. Government data suggests that around 50% of UK SMEs have experienced some form of cyber incident in the last two years. Two-thirds of those never report it, because of embarrassment or fear of reputational damage.
The good news: the five threats below are the same ones we've been dealing with for years. None of them require exotic new technology to stop — just proper, consistent security hygiene.
Business Email Compromise (BEC)
Business Email Compromise is now the single most financially damaging cybercrime affecting UK businesses. It works like this: an attacker impersonates a senior person — a CEO, a finance director, or a known supplier — and emails someone in accounts to request a payment to a new bank account. The email looks legitimate. The tone is right. And by the time anyone realises, the money is gone.
What's changed in 2026 is the sophistication. Attackers now use AI to study email patterns, mimic writing style, and wait for the right moment (end of quarter, annual leave, a major transaction). They use compromised legitimate accounts more than spoofed ones — so the email genuinely comes from a real business relationship.
How to protect against it
- Enforce MFA on all email accounts. This alone blocks the vast majority of account takeovers.
- Implement DMARC, DKIM, and SPF on your domain. These stop spoofing (email pretending to be from your domain).
- Verify payments by voice. Any bank change request should trigger a phone call to a known number — not the number in the email.
- Train your team. Most BEC attacks are stopped by someone pausing to ask "does this feel right?"
- Set up mailbox rules monitoring. Attackers often set up rules to auto-delete replies. We can flag suspicious rules automatically.
Ransomware
Ransomware is not new, but it remains the most disruptive attack for businesses of any size. Modern variants don't just encrypt your files — they exfiltrate data first, then threaten to publish it if you don't pay. This "double extortion" model means backups alone are not enough.
2026 trends: ransomware groups are increasingly targeting specific industries (legal, healthcare, manufacturing) where downtime is intolerable. They research targets thoroughly, and they know which businesses are likely to pay. Average ransom demand in the UK is now around £150,000 — with recovery costs often running 3–5× that.
How to protect against it
- Air-gapped backups. Backups must be physically or logically isolated from your production network — otherwise ransomware encrypts them too.
- Test your restores. We recommend quarterly full-restore tests. If you've never tested a restore, you don't have a backup plan.
- EDR on every endpoint. Modern endpoint detection and response tools spot ransomware behaviour and can often stop it mid-attack.
- Patch promptly. Most ransomware exploits known vulnerabilities. Patching closes that door.
- Segment your network. Flat networks let ransomware spread quickly. Segmented networks contain the damage.
Phishing and AI-generated social engineering
Phishing remains the #1 vector for initial compromise — over 90% of successful attacks start with a phishing email. What's changed is that AI has made phishing dramatically more convincing. Generic "Dear customer, please click this link" has been replaced with personalised messages that reference real projects, real colleagues, and real context pulled from LinkedIn, company websites, and social media.
Voice phishing (vishing) is also on the rise — attackers clone voices from a 30-second sample (from a podcast, YouTube video, or voicemail) and call employees pretending to be executives. Video deepfakes have been used in targeted CEO fraud attempts, with a notable case in the UK in early 2026 costing a business £220,000.
How to protect against it
- Email filtering at the gateway level, with advanced phishing detection (not just spam filters).
- Phishing simulation programme. Regular, realistic simulations that train people to spot the patterns — and to report them without fear.
- Verification protocols for financial transactions. A simple "callback on a known number" rule prevents most BEC and vishing attempts.
- Use code words or phrases for high-value verbal transactions with executives.
- Continuous awareness training. Not once-a-year box-ticking — short, frequent, relevant training that reflects current threats.
Supply chain attacks
Attackers are increasingly targeting not you, but the vendors and contractors you trust. If they can compromise a supplier (a payroll provider, a software vendor, an IT provider), they get access to every one of that supplier's clients at once. The 2020 SolarWinds attack was the most famous example, but 2025 and 2026 have seen a steady stream of smaller-scale supply chain compromises.
Common vectors: legitimate-looking software updates, unauthorised remote access tools, compromised SaaS accounts at the vendor level, and even targeted attacks on MSPs themselves. As a managed service provider ourselves, this threat is one we take seriously — both for our own security and for how we vet our own suppliers.
How to protect against it
- Vet your suppliers. Ask about their security certifications (Cyber Essentials, ISO 27001), and how they protect the access they have to your systems.
- Least privilege access. Suppliers should only have access to what they actually need — not full network access.
- Monitor supplier activity. Review logs of what suppliers do in your systems, especially outside agreed hours.
- Have an offboarding process. When a supplier's contract ends, remove their access systematically.
- Contractual security clauses. Require your suppliers to have security policies, notify you of incidents, and hold appropriate insurance.
Insider threats and account compromise
The "insider threat" doesn't always mean a malicious employee. More often, it's a legitimate account compromised by an attacker, or an employee who accidentally clicks something they shouldn't have. A compromised account can operate inside your network for months before detection — quietly exfiltrating data, setting up persistence, or moving laterally.
In 2026, insider threat incidents increasingly involve ex-employees whose accounts weren't properly deprovisioned, or contractors with overly broad access. We've seen cases where a former employee still had email access 8 months after leaving — and had been forwarding client emails to their new employer.
How to protect against it
- Structured offboarding process. Remove access on the day someone leaves — including email, cloud apps, VPN, building access, and third-party systems.
- Access reviews. Quarterly reviews of who has access to what, especially privileged accounts.
- User behaviour analytics. Flagging unusual activity — access outside normal hours, mass file downloads, unusual login locations.
- Principle of least privilege. Staff should have access to what they need to do their job — and nothing more.
- Data Loss Prevention (DLP). Controls to prevent sensitive data being emailed out, copied to USB drives, or uploaded to personal cloud accounts.
What this means in practice
None of these threats are unstoppable. But defending against them requires consistent effort on multiple layers — not a single "silver bullet" tool. The most secure businesses we work with share a few common traits:
- They have senior leadership buy-in on security being a priority, not a checkbox.
- They have proper access controls (MFA everywhere, least privilege, regular reviews).
- They have tested backups with an actual restore plan.
- They train their staff regularly — and reward people who report suspicious emails.
- They have a documented incident response plan, reviewed annually.
Security is not about being impenetrable. It's about being more difficult to attack than the next business — and being prepared to respond quickly when something does go wrong.
Where to start
If you're reading this and thinking "we probably have gaps", that's normal — most businesses do. The right first step is a proper audit, not a shopping list of tools.
Book a free 60-minute security review with us. We'll look at your current setup, identify the priority risks, and give you a written report — including a realistic action plan. No obligation, no sales pressure. Just an honest view of where you stand.