ISO 27001 certification: costs, process and duration explained

For mid-sized companies, the costs of an ISO 27001 certification start from €20,000 (fixed price after scoping) for consulting and building the ISMS — plus the separate audit fees of the accredited certification body. The entry point is a gap analysis for €3,500 (up to 50 employees) or €4,500 (50 employees or more), which determines the maturity of your information security management system and makes the implementation effort predictable. The largest cost item is building the policies, processes and evidence up to audit readiness. The project typically takes 3 to 9 months; the certificate is then valid for 3 years, and annual surveillance audits are added as ongoing costs. How high your ISO 27001 certification costs actually turn out to be depends on company size, the number of locations and the chosen scope.

Which costs arise for an ISO 27001 certification for small companies?

With ISO 27001 certification, you demonstrate that your ISMS meets an internationally recognized standard.

Determining the costs of an ISO 27001 certification starts with a gap analysis to prepare the subsequent steps. You also need to take into account targeted staff training, internal resource planning and carrying out internal audits.

Costs arise for implementing an information security management system (ISMS) and for the audits. External auditors from the certification body carry out the certification audit to verify conformity with the ISO 27001 standard.

The costs of implementation and certification according to ISO 27001 vary depending on the size and complexity of the company and depend on various factors, which we discuss below.

The costs of complying with ISO 27001 certification depend on the size of the business, the number of employees and the company's location. Companies must take into account the expenses for introducing the information security management system as well as the ongoing costs of surveillance audits and checks by external auditors. To optimize certification costs, we recommend ISO 27001 consulting at a fixed price — no day-rate risk during implementation, and the implementation remains efficient and economical.

Which internal and external components make up the costs of an ISO 27001 certification?

We have listed all phases and the associated costs for you, so that you get maximum transparency:

1. Audit of the current security situation

• • External audit costs for security experts, or internal resources that spend time and effort evaluating current security practices.

2. Building an ISMS (Information Security Management System)

• • Costs for developing and implementing a tailored ISMS, including adapting policies, procedures and processes.
• • Possible expenses for purchasing ISMS software or tools to manage the security measures.

3. Employee training

• • Costs for training and training materials to improve employees' security awareness.
• • Time spent by internal trainers or external training providers.

4. Certification fees

• • Fees charged by the accredited body for carrying out the certification audit.
• • The amount of the fees can vary depending on the size and type of company and the scope of the certification.
• • Costs for the certification body's review of the ISMS documentation and processes.
• • Possibly additional expenses for follow-up audits or corrections.

5. Required internal resource planning and how you can reduce it with external consulting

Aligning the time and staff resources required for the certification process and the subsequent management of the ISMS. Take these points into account in your resource planning:

• • Consulting on ISMS development:

    An external consultant can help develop and implement a tailored ISMS that meets the company's specific requirements.

• • Support with documentation:

    A consultant can help create and update the documentation and policies required for the ISMS.

• • Training and awareness:

    With consulting support, training and awareness measures can be delivered to employees to strengthen security awareness within the company

• • Preparing for certification:

    Support in preparing for the ISO 27001 certification audit, including internal audits, mock audits and identifying weaknesses, in order to optimize the costs of certification.

• • Specialist expertise:

    Access to specialist knowledge and internationally recognized best practices from other information security projects, to ensure that the ISMS meets current standards and requirements.

6. Technology investments

Procurement and implementation of security technologies such as firewalls, encryption solutions, etc.

7. Ongoing expenses

• • Costs for regular internal audits and reviews of the ISMS
• • Regular employee training to maintain security awareness

Process and duration of ISO 27001 certification

ISO 27001 certification runs in five steps: gap analysis, building the ISMS (policies, risk assessment, controls), operation including an internal audit and management review, then the two-stage certification audit – stage 1 reviews the documentation, stage 2 the day-to-day implementation. The certificate is then valid for three years, with a surveillance audit in each of the following years.

It typically takes 3 to 9 months to reach the certification audit. How fast it goes depends less on the size of the company than on the starting level and on how quickly decisions are made internally. We describe the setup step by step in building an ISMS according to ISO 27001.

What does the ISO 27001 certification audit cost?

The certification audit is carried out by an accredited certification body, which invoices you directly. The body determines the audit duration according to ISO/IEC 27006, mainly based on the number of employees in scope, adjusted for complexity and the number of sites. That is why audit costs rise with the size of the scope – a cleanly defined scope saves real money here. For the surveillance audits in the two following years, part of this audit time is incurred again; recertification follows in the third year.

What specific costs should small companies expect for external consulting?

Based on our experience, we have summarized the available consulting options for the relevant price range.

The costs can be divided into 3 parts, which are explained in detail:

      <strong>1. Gap analysis:</strong> A gap analysis is like a doctor's X-ray: it shows you the current situation and what needs to be done to achieve ISO 27001 certification. It is based on the ISO 27001 roadmap. It is carried out as a one-day workshop and costs <strong>€3,500</strong> (up to 50 employees) or <strong>€4,500</strong> (50 employees or more).

      <strong>2. Building the ISMS and policies:</strong> This is the most labor-intensive part of the ISO 27001 project – the structured build-up of the information security management system, including all required policies, procedures and processes.

      <strong>3. Maturity – establishing the processes and collecting evidence:</strong> In the final step, the defined processes are established in day-to-day business, the maturity level needed for the audit is built up, and the evidence for the certification audit is collected.

ISO 27001 consulting is available from €20,000 (fixed price after scoping). External consulting above all reduces the internal time spent on documentation, risk assessment and audit preparation.

The project duration can be between 3 and 9 months. And please do not forget that you also need to budget for the costs of the independent certification body.

Worth reading: The ISO 27001 certification process (in German)

For further information, schedule a meeting with us.

72% rely on external experts (TÜV study 2023) — what this means for your ISO 27001 budget

The costs of an ISO 27001 certification consist of internal effort, the certification body's audit fees and external consulting — and consulting is not an optional extra but common practice. According to the TÜV Cybersecurity Study 2023 [1], 72% of German companies seek advice from external experts to expand their security know-how; 51% also train their employees.

For budget planning, this means: external ISO 27001 consulting is the norm, not the exception. It shortens the project time up to the certification audit, reduces the risk of nonconformities and relieves internal IT and compliance resources. If you factor in consulting costs from the start, you avoid having to increase the budget between the Stage 1 and Stage 2 audits.

Sources:

[1] TÜV-Verband e. V. (ed.): TÜV Cybersecurity Studie 2023 — Cybersicherheit in deutschen Unternehmen (in German). Representative survey conducted by Ipsos among 501 companies with 10 or more employees. Berlin, June 12, 2023. (accessed on August 4, 2026).

Last updated: August 4, 2026