ISO 27001 – the ultimate UK guide [updated February 2025]
What is ISO 27001?
ISO 27001 is the international standard for Information Security. It provides a framework for an information security management system. This enables organisations to manage the security of assets like finance information, intellectual property, employee details or information entrusted by third parties.
ISO 27001 Explainer video
Is ISO 27001 mandatory in the UK?
ISO 27001 is not mandatory in the UK by law. However, some specific industries or contracts may require the certification. For example:
Government contracts: Some UK government contracts, particularly in sectors dealing with sensitive data, require suppliers to have have certification or similar robust security standards.
Financial and healthcare sectors: Organisations in heavily regulated industries like finance and healthcare may need to follow stringent information security protocols, and ISO 27001 can help demonstrate compliance.
What is the purpose of the ISO 27001 framework?
The ISO 27001 framework aims to help organisations protect their information by establishing an Information Security Management System (ISMS) focused on confidentiality, integrity, and availability. It provides a structured, risk-based approach to managing and mitigating security threats.
Who is ISO 27001 for?
ISO 27001 is a great tool for organisations of any size and in any sector to use to keep their information assets more secure. It allows the business to demonstrate that it complies with current international best practice, and that it is effectively securing information assets and managing the risks around them. It also ensures that the organisation constantly improves its systems and processes to fit evolving needs.
Why would I need ISO 27001?
- There are many UK laws, regulations, and contractual requirements related to information security, most of which can be resolved by implementing ISO 27001
- You can use it as a tool to manage GDPR compliance
- If your organisation’s ISMS gets ISO 27001 certified, you’ll have an advantage over competitors who don’t have the certification
- Bid for contracts with larger organisations that require the certification
- Minimise the evidence required for a larger organisation to complete its due diligence
- Identify your information assets and their value, so you can make informed decisions to mitigate risks and ensure efficient spending
- Lower monetary and reputational damage resulting from a security incident
ISO 27001 for UK SMEs: Is it worth it?
Many small businesses wonder if ISO 27001 is necessary for them. The answer depends on factors such as client expectations, industry regulations, and security risks. Benefits for SMEs include:
- Meeting security requirements for larger clients and government contracts.
- Reducing cyber risks and protecting sensitive data.
- Demonstrating a commitment to information security, which builds customer trust.
- Avoiding costly security incidents that could disrupt business operations.
ISO 27001 is scalable, meaning even smaller organisations can implement it in a cost-effective way. Securious’ ISO 27001 Academy provides an accessible route to compliance without the overhead of full consultancy.
ISO 27001 vs other UK information security standards
Organisations looking to improve their information security often compare ISO 27001 with other standards. Here’s how it compares to some key alternatives:
- Cyber Essentials: Cyber Essentials is a UK government-backed certification designed to help organisations protect against common cyber threats. It is simpler and focuses primarily on technical controls, whereas ISO 27001 provides a comprehensive framework for managing information security risks at an organisational level.
- NIST: The NIST Cybersecurity Framework is a US-based set of guidelines for improving cybersecurity risk management. Unlike ISO 27001, it is not a certifiable standard but provides useful best practices.
- ISO 9001: ISO 9001 focuses on quality management systems, while ISO 27001 is dedicated to information security. However, organisations often integrate both to demonstrate robust security alongside operational excellence.
What is an ISMS?
An Information Security Management System (ISMS) is a comprehensive framework of policies, processes, and controls that an organisation implements to manage its information security. The goal of an ISMS is to protect the confidentiality, integrity, and availability of information by systematically identifying and managing risks, and by implementing controls to address these risks.
ISO 27001 is a standard for creating and maintaining an ISMS. It is designed to be a continuous process that organisations can use to assess, mitigate, and monitor information security risks. It aligns with the Plan-Do-Check-Act (PDCA) cycle, which promotes continual improvement of security practices. Here’s how it works:
Plan: Identify risks and define information security objectives, policies, and controls needed for risk mitigation.
Do: Implement and operate the controls defined in the planning phase.
Check: Monitor and measure the effectiveness of the ISMS through audits and regular evaluations.
Act: Take corrective and preventive actions to continually improve the ISMS.
What are the three principles of ISO 27001?
As per the ISO 27001 definition, the basic goal of an Information Security Management System is to protect three aspects of information:
Confidentiality: Only authorised persons have the right to access information.
Integrity: Only authorised persons can change the information.
Availability: The information must be accessible to authorised persons whenever needed.
How do I get an ISO 27001 certification in the UK?
An organisation can achieve certification by implementing an Information Security Management System (ISMS) using the ISO 27001 framework. This involves creating policies, procedures, and processes.
Once implemented, it’s wise to carry out a full internal audit. A company like Securious can provide an independent review to ensure your ISMS is complete and effective.
When you’re confident your ISMS meets ISO 27001 standards, engage an external auditor, such as BSI, for the certification audit. This audit has two stages: a review of your documentation and a detailed assessment of your ISMS.
If the auditor confirms compliance, you’ll receive certification. To maintain it, you’ll need regular audits and ongoing ISMS improvements.
Securious, based in Exeter, supports hundreds of ambitious organisations locally, across the UK, and internationally. Contact us below to start your ISO 27001 journey.
How do I achieve certification?
There are several steps involved in achieving ISO 27001:
- Firstly, it’s important to have a solid understanding of ISO 27001. This includes what it is, and the importance of managing your assets, risks and incidents. At this stage, it is important to determine your scope and understand the Plan, Do, Check, Act approach (which you may be familiar with through HSE).
- The next step covers the importance of leadership and identifying your Information Security Management System (ISMS) team, allocation of resources, competence, and communication.
- Then we can move on to the planning stage, creating objectives and deciding how we’ll achieve them
- The planning stage also includes identifying information assets and building an asset register so that you can move on to identifying the risks to these assets.
- Risk assessment is also part of the planning stage, including risk methodology, risk assessments and building the risk register
- The final part of the planning involves determining risk treatment to mitigate the risks to an acceptable level.
- At this stage we also create the Statement of Applicability. This takes all the controls in Annexe A and determines whether they are applicable
- Once you understand what you are protecting and the controls you have identified, you can implement the plans to mitigate risks that your information assets may be exposed to.
- Performance Evaluation and improvement helps us to check that what we have put in place is working and then feed this back into opportunity for improvement. This will include internal audits, and feedback into the ISMS Team.
How often do you need to renew ISO 27001 certification?
ISO 27001 certification is valid for three years, but maintaining it requires ongoing commitment:
- Annual surveillance audits – Certification bodies conduct yearly audits to ensure continued compliance.
- Recertification audit (Year 3) – Organisations must undergo a full recertification audit at the end of the three-year cycle to maintain certification.
- Ongoing ISMS improvements – Businesses should continuously review and enhance their ISMS to align with evolving risks and best practices.
How much does ISO 27001 certification cost in the UK?
The cost of ISO 27001 certification varies depending on the size of your organisation and the approach you take. Key cost factors include:
- Consultancy fees – Many businesses engage an ISO 27001 consultant to streamline implementation.
- Certification body fees – Accreditation bodies charge for the initial audit and ongoing surveillance audits.
- Internal resource allocation – Time spent by staff on risk assessments, documentation, and internal audits.
For a cost-effective route to certification, Securious offers the ISO 27001 Academy, which provides structured guidance through a series of online workshops at a fixed price of £2,895 +VAT.
About implementation
The implementation will involve the completion of relevant policies, procedures and forms and the ISMS manual to communicate how to maintain the Information Security Management System. We normally phase these within steps, so that this is not simply a document completion exercise, but something that fulfils the need at that particular stage.
Once implementation is complete, then you are ready for a stage one audit to determine that you have an ISMS in place.
This is followed by a stage two audit which then checks to see if the ISMS is working.
Once the accreditation body is satisfied that you have met the standard, they will issue you with your certification.
The most important goal for us is to share knowledge and ensure that the organisation implementing ISO 27001 is competent and confident to maintain this system as part of their business as usual.
Common challenges in ISO 27001 implementation
Many organisations face hurdles when implementing ISO 27001. Some of the most common challenges include:
- Lack of internal expertise – Without prior experience, organisations can struggle to interpret the standard and apply it effectively.
- Resource constraints – Implementing an ISMS requires investment in time, personnel, and potentially external support.
- Employee engagement – Achieving ISO 27001 compliance requires organisation-wide participation, which can be difficult to secure.
- Risk assessment complexity – Identifying and assessing risks systematically can be challenging, especially for organisations with complex IT environments.
A trusted ISO 27001 consultancy, such as Securious, can help navigate these challenges and ensure a smooth implementation process.
How long does it take?
We have managed to implement ISO 27001 within a 12 week process for some clients. However generally an implementation takes around 3-6 months (sometimes longer depending on resource availability and scope of the organisation)
How much does it cost?
We tailor our ISO 27001 consultancy service to your individual needs and circumstances. So please get in touch and we’ll provide you with a quote based on your situation and requirements.
Alternatively, we’ve pioneered the Securious ISO 27001 Academy. We work with businesses in a series of online workshops, for just £2,895 +VAT which includes all the necessary templates.
ISO 27001 compliance vs certification
Being ISO 27001 compliant means following the standard’s guidelines and practices. Being ISO 27001 certified means undergoing a formal audit process to prove compliance and earning an official certification. Certification can enhance trust and market opportunities but requires a greater commitment in terms of both resources and ongoing maintenance.
Two parts of the standard
The ISO 27001 standard is divided into two main parts:
1) Clauses 0–10 (Main Requirements): This part defines the requirements for establishing, implementing, maintaining, and continually improving an Information Security Management System (ISMS). Clauses 4 through 10 are mandatory for compliance:
- Clause 4: Context of the Organisation
- Clause 5: Leadership
- Clause 6: Planning
- Clause 7: Support
- Clause 8: Operation
- Clause 9: Performance Evaluation
- Clause 10: Improvement
2) Annex A (Control Objectives and Controls): This part lists 93 specific controls that are organised into four sections (A.5–A.8). These controls address various security areas and are not mandatory but serve as a reference to meet the risk treatment requirements. You can learn more about them in the sections below.
Main requirements of the standard
Here’s more information about Clauses 0–10 of the ISO 27001 standard. These are the core requirements for establishing and operating an ISMS:
Clause 0: Introduction
Clause 0 is an introductory section that outlines the standard’s purpose and scope. It explains how ISO 27001 can help organisations manage risks to information security.
Clause 1: Scope
This outlines where and how ISO 27001 should be applied, helping organisations identify what aspects of their operations the ISMS will cover.
Clause 2: Normative References
This section provides links to standards related to ISO 27001 that can be referenced for additional guidance.
Clause 3: Terms and Definitions
In this clause, key terms that are used throughout the standard are clarified and defined. For example, explaining what constitutes an “ISMS” and “control”. Providing suitable explanations for these key terms ensures consistency in reader interpretation.
Clause 4: Context of the Organisation
This section emphasises understanding the internal and external factors affecting the ISMS. Organisations must analyse influences like regulatory demands, customer requirements, and internal policies to define the ISMS’s scope accurately.
Clause 5: Leadership
This section stresses the significance of leadership commitment. This clause requires top management to endorse and support the ISMS, set security policies, and assign roles and responsibilities for information security within the organisation.
Clause 6: Planning
Organisations are required to identify risks and opportunities relevant to information security, set objectives, and plan actions to manage those risks. A key component here is the information security risk assessment and the development of a risk treatment plan, with actions for addressing identified risks.
Clause 7: Support
This clause outlines the necessary support mechanisms for the ISMS, including resources, staff competence, and communication. It also requires maintaining appropriate documentation to support effective ISMS operation.
Clause 8: Operation
In this stage, the organisation must implement risk assessment and treatment plans, along with all operational processes required for information security. This clause focuses on putting planned controls into action and monitoring their effectiveness.
Clause 9: Performance Evaluation
Regular monitoring and evaluation are necessary to ensure the ISMS’s effectiveness. This clause requires internal audits, performance evaluations, and management reviews to gauge the ISMS’s performance and identify improvement areas.
Clause 10: Improvement
The standard encourages continual improvement by identifying and addressing nonconformities. Organisations must establish corrective actions and enhance their ISMS processes over time, even though a specific improvement cycle is not mandated.
Together, Clauses 0–10 provide a comprehensive framework for establishing an ISMS that aligns with an organisation’s needs, ensuring that information security practices are effective, sustainable, and capable of evolving as risks and requirements change.
How many controls are there in ISO 27001?
ISO 27001 controls are a set of practices or safeguards that help an organisation manage information security risks. The 2022 revision of ISO 27001 organises these 93 controls into four main categories.
What are the ISO 27001 controls?
A.5 – Organisational Controls
Focuses on management practices, policies, and processes to maintain information.
A.6 – People Controls
Focuses on security awareness, skills, and human resources management.
A.7 – Physical Controls
Focuses on securing the physical environment and assets to prevent unauthorised access.
A.8 – Technological Controls
Focuses on securing information and IT systems.
How do you implement the controls?
To implement the controls, organisations typically follow a structured process within the framework of an ISMS. Here’s a simplified approach:
- Identify the scope of the ISMS (which information assets and departments are included), then set clear security objectives aligned with business goals.
- Identify risks to information security. Evaluate their impact and probability of occurring and prioritise them. This will help you determine which controls are necessary.
- Choose relevant controls based on the risk assessment. Once selected, document them in a Statement of Applicability.
- Then develop policies and procedures aligned with the chosen controls. For example, if you’ve selected access control, create policies defining who can access specific information.
- Implement your selected controls.
- Regularly monitor and review the controls’ effectiveness. You can conduct internal audits, and update processes as needed.
- ISO 27001 follows a continuous improvement model. Use audit findings, incident reports, and feedback to refine and strengthen controls over time.
What is ISO 27000?
ISO 27001 is a part of the ISO 27000 family. This is a group of standards focusing on information security management, designed to help organisations keep their information assets secure. Here are some other key standards in the ISO 27000 family:
- ISO/IEC 27002: Code of Practice for Information Security Controls
- ISO/IEC 27003: Information Security Management System Implementation Guidance
- ISO/IEC 27004: Information Security Management – Monitoring, Measurement, Analysis, and Evaluation
- ISO/IEC 27005: Information Security Risk Management
- ISO/IEC 27017: Code of Practice for Information Security Controls for Cloud Services
- ISO/IEC 27018: Protection of Personally Identifiable Information (PII) in Public Clouds
- ISO/IEC 27031: Guidelines for ICT Readiness for Business Continuity
- ISO/IEC 27032: Guidelines for Cybersecurity
- ISO/IEC 27033: Network Security
- ISO/IEC 27701: Privacy Information Management System (PIMS)
- ISO/IEC 27040: Storage Security
FAQs About ISO 27001
Can I self-certify ISO 27001?
No, organisations cannot self-certify ISO 27001. An independent, accredited certification body must verify compliance. However, businesses can implement the framework internally without official certification if they only need compliance rather than formal validation.
Do I need an ISO 27001 consultant?
While not mandatory, working with an ISO 27001 consultant can make the process significantly smoother. Consultants help with interpreting the standard to align with your environment and business-as-usual (BAU) operations, conducting risk assessments, and preparing documentation. They can also provide pre-audit checks to ensure your organisation is ready for certification.
Does ISO 27001 cover GDPR compliance?
ISO 27001 and GDPR are complementary but not identical. Implementing ISO 27001 helps organisations establish strong data protection measures, reducing GDPR compliance risks. However, GDPR includes additional requirements around personal data rights and processing transparency, which ISO 27001 does not specifically address, but should be considered as part of the risk process.
What happens if I fail an ISO 27001 audit?
If an organisation fails an audit, the certification body will issue non-conformities that must be resolved. Minor issues can be corrected and verified before certification is granted. Major non-conformities may require a follow-up audit to confirm corrective actions.
Is ISO 27001 only for IT companies?
No, ISO 27001 applies to any organisation handling sensitive information, regardless of industry. While technology firms often pursue certification, businesses in healthcare, finance, manufacturing, and professional services also benefit from an ISMS.
What Is the difference between ISO 27001 and ISO 27002?
ISO 27001 and ISO 27002 are complementary standards within the ISO 27000 family, each serving distinct purposes. ISO 27001 outlines the requirements for establishing, implementing, maintaining, and continually improving an Information Security Management System (ISMS). It provides a risk-based framework to manage sensitive company information systematically. In contrast, ISO 27002 offers guidelines and best practices for implementing the information security controls listed in Annex A of ISO 27001. While ISO 27001 is certifiable, meaning organisations can be audited and certified against it, ISO 27002 is not intended for certification but serves as a practical guide to implement controls effectively.
Can ISO 27001 be integrated with other standards?
Yes, ISO 27001 can be integrated with other standards, such as ISO 9001 (Quality Management) and ISO 22301 (Business Continuity Management). These standards share common structures and principles, facilitating a unified approach to management systems. Integrating these standards can streamline processes, reduce duplication of efforts, and create a cohesive management system that addresses multiple aspects of an organisation’s operations. For instance, organisations can align their information security objectives with quality and business continuity goals, ensuring a comprehensive and efficient management strategy.
What are the penalties for non-compliance with ISO 27001 in the UK?
ISO 27001 is a voluntary standard; therefore, there are no legal penalties for non-compliance. However, failing to implement adequate information security measures can lead to significant risks, including data breaches, financial losses, reputational damage, and loss of customer trust. Additionally, if an organisation has contractual obligations requiring ISO 27001 certification, non-compliance could result in breach of contract and associated legal consequences. In addition to this, inadequate information security practices may lead to non-compliance with legal requirements such as GDPR, which does impose substantial fines for data protection violations.
How does ISO 27001 address cloud security?
ISO 27001 addresses cloud security by requiring organisations to assess and manage risks associated with cloud services within their ISMS. This includes evaluating cloud service providers, implementing appropriate controls to protect data stored or processed in the cloud, and ensuring compliance with relevant legal and contractual requirements. The 2022 revision of ISO 27001 places enhanced emphasis on cloud security considerations, reflecting the growing reliance on cloud services. Organisations are encouraged to implement controls that address cloud-specific risks, such as data segregation, access management, and monitoring of cloud environments.
How can Securious help with ISO 27001?
Securious’ ISO 27001 services will provide you with:
- Qualified ISO 27001 practitioners (Lead Implementers and Lead Auditors)
- Our ISO 27001 Academy, where we work with you in a series of collaborative, interactive workshops
- Bespoke consultancy as required
- Full document set and ISO 27001 templates
- 100% success rate helping clients achieve and maintain ISO 27001
ISO 27001 consultancy
We offer bespoke consultancy as well as the pioneering Securious ISO 27001 Academy, where we work with businesses in a series of collaborative, interactive online workshops.
ISO 27001 Academy
With the Securious ISO 27001 Academy, we work with businesses in a collaborative, interactive workshop for a more effective (and cost-effective) implementation. This can be done in-person or remotely.
Over 6 sessions, each business will gain an understanding of the standard, its application and implementation, while building an information security management system manual – a core document required for ISO 27001. The following will be covered in the six two-hour workshops.
- What is ISO 27001 and how can this assist with GDPR compliance
- Leadership requirements and support for ISO 27001
- Planning and asset management
- Introduction to risk assessment
- Introduction to risk treatment
- Introduction to performance evaluation
Our academy will help any business or organisation looking to implement an information security system that helps them align with – and achieve – ISO 27001, the International Standard for Information Security.
How to get started
If you’re interested in achieving ISO 27001, get in touch using the contact form below.