Not sure whether to train as an ISO 27001 Internal Auditor or Lead Auditor? You’re not alone – it’s one of the most common questions we hear.

This blog post explains what each course covers, who they suit, the core differences between them and how to decide which one is right for you.

What the ISO 27001 Internal Auditor course covers

The ISO 27001 Internal Auditor course teaches you how to plan and deliver in-house ISMS (information security management system) audits. You learn to test controls against ISO/IEC 27001:2022, record nonconformities and report findings that drive corrective action.

It focuses on practical audit execution inside your organisation, covering the audit cycle from end to end, including scoping, preparing checklists, interviewing control owners, sampling evidence, writing clear findings and following up on remediation. You also learn how internal audits support certification and the continual improvement of the ISMS.

Typical audience

• In-house information security, IT, risk, compliance or quality staff.
• ISMS contributors who need to evidence control effectiveness.
• Managers preparing for certification audits and surveillance visits.

Outcomes and value

• Run effective internal audits aligned with ISO 19011 guidance.
• Identify weaknesses and raise clear, actionable nonconformities.
• Improve audit readiness.
• Build confidence to support your ISMS year-round.

Career impact

• A strong foundation for roles such as ISMS manager, compliance officer, GRC analyst, internal audit lead.
• A practical first step if you later plan to progress to Lead Auditor.

For new starters in ISO 27001, pairing Internal Auditor with Foundation training is a common route.

What the ISO 27001 Lead Auditor course covers

The ISO 27001 Lead Auditor course prepares you to lead external audits of third-party organisations. You learn to establish, maintain and manage an audit programme, assess and evaluate an audit team, and report to certification bodies or clients with clear conclusions.

It emphasises leadership, risk-based thinking and the consistency needed for high-stakes, multi-site engagements.

Typical audience

• Consultants and experienced practitioners who assess third parties.
• External auditors and those aiming to work with certification bodies.
• Professionals moving into audit leadership or assurance management.

Outcomes and value

• Plan and lead full-scope Stage 1 and Stage 2 audits against ISO 27001.
• Manage auditors, allocate tasks and quality-review evidence.
• Produce audit reports suitable for clients and certification bodies.
• Demonstrate audit competence that stands up to formal scrutiny.

Career impact

• Progress to roles such as external auditor, certification consultant, audit manager or assurance lead.
• Build credentials sought by consultancies and conformity assessment bodies.

Key differences at a glance

Purpose and context

• Internal Auditor training is designed to help you audit your own ISMS. It’s practical, focused on your internal controls and business context.
• Lead Auditor training is designed for auditing other organisations. It’s advanced, and emphasises impartiality, team leadership and reporting to external stakeholders.

Experience expectations

• Internal Auditor assumes basic ISO 27001 knowledge and little formal audit experience. It teaches you both the method and the mechanics.
• Lead Auditor expects solid familiarity with ISO 27001 and prior audit exposure.

Depth and scope

• Internal audits are scoped to your organisation’s risks, controls and processes.
• Lead audits test full conformity to the Standard and applicable scope statements in unfamiliar environments. The evidence burden, stakeholder management and judgement calls are greater.

Duration and assessment

• Our ISO 27001 Internal Auditor course is two days long, with a 60-minute exam.
• Our ISO 27001 Lead Auditor course is five days long, with a 90-minute exam.

Honest guidance: which should you take?

• If you work in-house and are new to auditing, choose Internal Auditor
  It gives you the skills you need now to support your ISMS and prepare for certification. It is the most efficient starting point for most internal teams.
• If you intend to audit suppliers, or work for a certification body or consultancy, choose Lead Auditor
  It equips you to lead external audits, manage audit teams and produce reports for clients and certification bodies.
• Still unsure? Start with Internal Auditor
  You will build audit fundamentals in a familiar setting, deliver immediate value to your organisation and keep the door open to Lead Auditor later. Progression from Internal to Lead is a well-trodden path.

Decision table

Factor	Internal Auditor	Lead Auditor
Audience	In-house compliance, IT, information security, risk and quality management staff	Consultants, external auditors, assurance leads
Primary goal	Audit your own organisation’s ISMS and support certification readiness	Audit third-party organisations against ISO 27001
Focus	Practical, in-house audit execution and improvement	Planning and leading external audits and teams
Experience needed	Basic ISO 27001 knowledge; audit experience helpful but not essential	Prior audit experience strongly preferred; confidence with ISO 27001 required
Typical duration	Shorter; concentrated on internal audit skills	Longer; intensive with leadership and reporting components
Assessment	Knowledge test and practical exercises	Continuous skills assessment plus formal exam
Career path	ISMS manager, compliance officer, GRC analyst, internal audit lead	Certification auditor, consultant, audit manager, assurance lead

Book your ISO 27001 auditor training with IT Governance

Both courses are valuable. The right choice depends on your role, objectives and timeline. Explore our ISO 27001 Internal Auditor and Lead Auditor courses to find the path that fits your career.