What Is Endpoint Security? A Guide for UK SMEs

What Is Endpoint Security?

Endpoint security refers to the tools and practices used to protect devices — or endpoints — that connect to a business network or access corporate data. As a fundamental layer of any cybersecurity strategy, endpoint security addresses the reality that every device capable of connecting to company systems represents a potential entry point for attackers. Endpoint security is the set of controls applied directly to those devices to detect, prevent, and respond to threats before they can spread across the organisation.

As workforces have become more distributed and as cloud services have replaced on-premises infrastructure, the device itself has become the primary security boundary. The traditional approach of protecting a network perimeter is no longer sufficient when employees access company data from home offices, client sites, and coffee shops. Effective endpoint security must travel with the device — protecting it regardless of location or network connection.

The need for robust endpoint protection is underscored by the threat landscape facing UK businesses. According to the DSIT Cyber Security Breaches Survey 2025, 43% of UK businesses experienced a cybersecurity breach or attack in the past twelve months, with 67% of medium businesses and 74% of large businesses reporting breaches (DSIT Cyber Security Breaches Survey 2025). Many of these breaches begin at the endpoint — through a phishing email opened on a laptop, malware downloaded onto a workstation, or a compromised mobile device.

What Counts as an Endpoint?

An endpoint is any device that connects to a business network or cloud service. For UK SMEs, the most common endpoints include:

• Laptops and desktop computers (Windows, macOS) — the primary devices used by office-based and remote workers
• Mobile phones and tablets (iOS, Android) — including personal devices used for work under bring-your-own-device (BYOD) policies
• Servers — both on-premises physical servers and cloud-hosted virtual machines running in Azure, AWS, or similar platforms
• Network-attached storage (NAS) devices that hold shared files and backups
• Point-of-sale terminals, specialist equipment, and industrial control systems in certain sectors

For most UK SMEs, the primary concern is laptops, desktops, and mobile devices — but any device with access to corporate data should be considered within scope for endpoint security. The proliferation of remote working since 2020 has significantly expanded the endpoint landscape for many businesses, with devices operating outside the protection of the office network.

Traditional Antivirus vs Modern EDR

Traditional Antivirus

Traditional antivirus software works by scanning files and comparing them against a database of known malicious signatures. If a file matches a known threat, it is quarantined or deleted. This approach is effective against established, well-documented malware but provides no protection against threats that have never been seen before — a significant limitation in an environment where attackers routinely create new malware variants specifically to evade signature-based detection. Traditional antivirus is a passive, reactive tool: it waits for a known threat to appear and then blocks it. It cannot detect fileless attacks, living-off-the-land techniques, or sophisticated multi-stage intrusions.

Modern EDR (Endpoint Detection and Response)

Endpoint detection and response (EDR) takes a fundamentally different approach. Instead of relying solely on known signatures, EDR continuously monitors endpoint behaviour — watching process activity, network connections, file modifications, registry changes, and user behaviour in real time. It uses machine learning and behavioural analytics to detect patterns consistent with malicious activity, regardless of whether the specific malware has been seen before.

When EDR detects a threat, it can automatically isolate the affected device from the network, terminate malicious processes, roll back file changes, and alert the security team for investigation. This combination of detection and active response is why EDR has replaced traditional antivirus as the standard for business endpoint protection. The distinction is important: antivirus is a single layer of passive defence, whilst EDR provides active, intelligent, and responsive protection.

Key Differences at a Glance

• Antivirus detects known threats by signature matching; EDR detects unknown threats by behavioural analysis
• Antivirus operates silently until a known threat is found; EDR continuously monitors and generates actionable intelligence
• Antivirus cannot isolate devices or contain incidents; EDR can automatically quarantine compromised endpoints
• Antivirus provides no investigation capability; EDR records detailed telemetry that analysts use to understand how an attack unfolded
• Antivirus requires manual updates to remain effective; EDR uses cloud-based machine learning that adapts in real time

How AI-Based Detection Works

Modern EDR platforms — including Microsoft Defender for Business and Huntress — use machine learning models trained on billions of endpoint events collected from organisations worldwide. These models establish a baseline of normal behaviour for each device and user, then flag deviations that match known attack patterns or anomalous activity sequences.

AI-based detection can identify never-before-seen malware variants by recognising behaviours common to malicious software — such as attempting to disable security tools, encrypting files in rapid succession, or establishing covert network connections. It can detect fileless attacks that operate entirely in memory without writing files to disk, and living-off-the-land attacks that misuse legitimate system tools like PowerShell or Windows Management Instrumentation for malicious purposes. This capability is essential because the DSIT Cyber Security Breaches Survey 2025 found that 85% of breaches involved phishing (DSIT Cyber Security Breaches Survey 2025), and phishing emails frequently deliver payloads designed to evade traditional signature-based detection.

What Managed Endpoint Security Includes

Managed endpoint security goes beyond simply deploying EDR software on devices. A comprehensive managed endpoint security service includes:

• Deployment and configuration of EDR agents on all endpoints, with policies tailored to your organisation's risk profile
• Continuous monitoring of EDR alerts by qualified security analysts, distinguishing genuine threats from false positives
• Active threat investigation — when an alert is triggered, analysts examine the full context to determine the scope and severity of the threat
• Incident containment — isolating compromised devices, terminating malicious processes, and revoking compromised credentials
• Remediation guidance — providing clear instructions for recovery, including re-imaging devices, restoring data, and strengthening defences
• Patch management support — ensuring operating systems and applications are kept up to date to close known vulnerabilities
• Monthly reporting on endpoint security status, threat volumes, and remediation actions taken

The DSIT Cyber Security Breaches Survey 2025 found that only 14% of UK businesses have a formal incident response plan (DSIT Cyber Security Breaches Survey 2025). Managed endpoint security fills this gap by providing expert response capability whenever an endpoint threat is detected, at any hour of the day or night.

Microsoft Defender for Business vs Huntress

For UK SMEs on Microsoft 365, Microsoft Defender for Business is the primary endpoint protection solution. It provides EDR capability, automated investigation and response, attack surface reduction rules, and network protection — all managed through the Microsoft 365 Defender portal. Microsoft Defender for Business is included in Microsoft 365 Business Premium, making it a cost-effective choice for SMEs already using the Microsoft platform.

Huntress is a managed EDR layer that can be deployed on top of Microsoft Defender, adding twenty-four-hour, seven-day human-led threat hunting and incident response by a team of dedicated security analysts. Where Microsoft Defender provides the detection technology, Huntress provides the human expertise to investigate alerts, eliminate false positives, and respond to confirmed threats. AMVIA deploys both as part of its managed endpoint security service, combining the Microsoft platform with Huntress for businesses that need around-the-clock human oversight.

24/7 SOC Monitoring for Endpoints

EDR software detects threats — but someone must investigate and respond to the alerts it generates. A Security Operations Centre (SOC) provides continuous human monitoring of endpoint alerts, triaging events, investigating genuine threats, and containing incidents before they escalate. For SMEs without in-house security staff, a managed EDR service with twenty-four-hour SOC coverage ensures that threats are responded to at any hour, not just during business hours when someone happens to check the dashboard.

The importance of rapid response cannot be overstated. Ransomware can encrypt an entire network in under an hour. Credential theft can give an attacker persistent access that they exploit days or weeks later. Without continuous monitoring, these threats can persist undetected, causing far greater damage than if they had been caught and contained immediately.

Cost of Managed EDR for UK SMEs

Managed endpoint detection and response for UK SMEs typically costs between £5 and £15 per device per month, depending on the provider, the scope of coverage, and whether twenty-four-hour SOC monitoring is included. For a fifty-person business with sixty endpoints, this represents approximately £3,600 to £10,800 per year — a fraction of the cost of hiring even a single in-house security analyst at £40,000 to £60,000 per year. The average cost of the single most disruptive breach was approximately £1,205 for micro and small businesses (DSIT Cyber Security Breaches Survey 2025), but the operational disruption, data loss, and reputational damage from a serious endpoint compromise can far exceed this figure.

How AMVIA Secures Endpoints for UK SMEs

AMVIA deploys and manages Microsoft Defender for Business on all client endpoints, supplemented with Huntress for twenty-four-hour threat hunting and human-led response. We manage patching, monitor alerts, investigate incidents, and provide monthly reporting on endpoint security status. Our Sheffield-based team is available around the clock to respond to genuine threats — giving your business enterprise-grade endpoint protection at a predictable monthly cost. With 43% of UK businesses experiencing a breach or attack in 2025 (DSIT Cyber Security Breaches Survey 2025), ensuring that every device in your organisation is actively protected and monitored is not a luxury — it is a fundamental business requirement.