What does ISO 27001 certification cost?
The costs of ISO 27001 certification vary widely. You need an accredited certification body , accredited by the Dutch Accreditation Council (RVA). You can buy the standard itself from NEN , the Dutch standards institute. The total investment depends on company size, the complexity of your IT environment and how much you have already arranged in the area of information security.
One thing is clear: ISO 27001 certification is a serious investment. It is not a quality mark you get quickly. It takes time, money and attention. But for many organisations, the investment outweighs the benefits: new customers, lower risks and demonstrable compliance.
The amounts in this article are indications based on market data from 2024-2025. Actual costs depend on your specific situation. Always request concrete quotes for an accurate estimate.
The total ISO 27001 investment in perspective
Before we break down the costs, it helps to sketch the full picture. The costs of ISO 27001 certification fall into two categories: the one-off implementation costs to obtain the certificate, and the ongoing costs to keep it.
| Cost item | Small (1-25) | Medium (25-100) | Large (100+) |
|---|---|---|---|
| Guidance and advice | €5,000 - €15,000 | €15,000 - €40,000 | €40,000 - €100,000+ |
| Purchasing the standard | €250 | €250 | €250 |
| Tooling and adjustments | €1,000 - €5,000 | €5,000 - €20,000 | €20,000 - €100,000+ |
| Certification audit | €4,000 - €8,000 | €8,000 - €15,000 | €15,000 - €40,000 |
| Internal audit | €1,000 - €2,000 | €2,000 - €5,000 | €5,000 - €15,000 |
| Staff training | - | €2,000 - €5,000 | €5,000 - €20,000 |
| Total first year | €11,000 - €30,000 | €32,000 - €85,000 | €85,000 - €275,000+ |
| Annual maintenance | €4,000 - €8,000 | €10,000 - €20,000 | €25,000 - €60,000+ |
Small business or SME? Expect €11,000 to €30,000 in the first year and a lead time of 4 to 6 months. With a smart scope and outsourcing, the costs are often lower. Read how to keep it feasible and affordable at ISO 27001 for a small business.
What do the costs of ISO 27001 consist of?
To understand where your money goes, we walk through the main cost items.
The standard itself
The ISO/IEC 27001:2022 standard is available from NEN for about €250. It is the official text that describes the requirements you must meet. You need this document to know exactly what is asked.
ISO/IEC 27002:2022 is also useful as an additional source. This standard gives detailed implementation guidance for the controls in Annex A. The price is comparable.
Guidance and advice
Most organisations bring in external expertise for ISO 27001 implementation. This can range from a consultant who guides the whole process to targeted support on specific parts.
Advice is often the largest cost item, especially for organisations with little experience of management systems. An experienced consultant can make the difference between a smooth implementation and a long, stumbling process. Good consultants know the standard inside out, know what auditors look for, and can help you avoid pitfalls.
Rates for ISO 27001 consultants range from €100 to €200 per hour, depending on experience and reputation. Some consultants work with fixed project prices, which gives more certainty about total costs.
It is also possible to work without a consultant, but this requires considerable effort from your own team. You must study the standard thoroughly, develop everything yourself and find any mistakes yourself. For a first certification, we recommend guidance, especially if you have no experience with similar standards.
Tooling and technical adjustments
ISO 27001 requires certain technical measures. Depending on your current security level, these may involve costs.
Think of investments in:
Security tooling such as SIEM systems for logging and monitoring, vulnerability scanners, endpoint protection or identity management solutions. The costs vary enormously, from a few hundred euros per month for cloud-based solutions to tens of thousands of euros for enterprise-grade systems.
Infrastructure adjustments such as network segmentation, stronger access protection or improved back-up systems. If your current infrastructure is already reasonably secure, these costs may be limited.
A document management system to manage your ISMS (information security management system) documentation. This can range from a simple wiki or SharePoint environment to specialised GRC software (Governance, Risk & Compliance).
Not all organisations need large investments in tooling. If you already use modern cloud platforms such as Microsoft 365 or Google Workspace, you often already have many security features available that you can configure.
The certification audit
The certification body sets the costs of the certification audit, which depend on the size and complexity of your organisation. We cover this item in detail below, at What does the ISO 27001 audit cost?.
Annual surveillance audits
After certification, the auditor returns every year for a surveillance audit. This is shorter than the initial audit, usually about half the time. After three years, a recertification audit follows, comparable to the initial audit.
Also budget time and costs for preparing these audits. Every year you must update your ISMS, carry out internal audits and hold management reviews.
Internal costs
Besides the external costs, there are considerable internal costs in the form of staff time. ISO 27001 implementation requires people at several levels:
The project manager who leads the process spends a significant part of their time on the project during implementation. In small organisations this can run alongside regular work. In larger organisations it is often a (near) full-time role.
IT and security specialists are needed for the technical implementation of controls, the risk assessment and setting up monitoring.
Management must be involved in policy decisions, the management review and freeing up resources.
All employees must be trained in security awareness and must work according to the new procedures.
A common mistake is underestimating these internal costs. If you do not free up capacity, the process is delayed or carried out superficially, which causes problems later.
For a small business, plan for 200-400 internal hours during the implementation process. For a medium-sized business this can rise to 500-1,000 hours or more.
What does the ISO 27001 audit cost?
The ISO 27001 audit costs a small business an indicative €4,000 to €8,000, a medium-sized business €8,000 to €15,000, and a large organisation €15,000 to €40,000. These are the amounts from the table above. The price depends on the number of audit days, and that number depends on how many employees you have.
The audit consists of two phases. Phase 1 is a documentation review, which usually takes half a day to a full day. Phase 2 is the implementation audit on site. Its duration depends on the number of employees and the complexity of your organisation.
The number of audit days is set according to guidelines from the International Accreditation Forum (IAF) . As an indication:
| Number of employees | Audit days (Phase 1 + 2) |
|---|---|
| 1-10 | 2-3 days |
| 11-25 | 3-4 days |
| 26-45 | 4-5 days |
| 46-65 | 5-6 days |
| 66-85 | 6-7 days |
| 86-125 | 7-8 days |
Daily rates of auditors range from €1,000 to €1,500 per day. Well-known bodies in the Netherlands include Kiwa , BSI , TÜV , DNV , Bureau Veritas and LRQA . Compare quotes, but do not look only at price. The quality of the auditor and their experience in your sector also count. Read more about the audit process.
After the first year, the auditor returns for an annual surveillance audit. That is shorter and therefore cheaper, as described under annual surveillance audits.
Lead time: how long does it take?
The lead time depends on the same factors as the costs: size, complexity and your current security level.
| Phase | Small (1-25) | Medium (25-100) | Large (100+) |
|---|---|---|---|
| Orientation and gap analysis | 2-3 weeks | 3-4 weeks | 4-8 weeks |
| Risk assessment | 2-3 weeks | 4-6 weeks | 6-10 weeks |
| Setting up and documenting the ISMS | 4-6 weeks | 6-8 weeks | 8-16 weeks |
| Implementing controls | 4-8 weeks | 8-12 weeks | 12-24 weeks |
| Internal audit and management review | 1-2 weeks | 2-3 weeks | 4-6 weeks |
| Certification audit | 2-3 days | 3-5 days | 5-10 days |
| Total lead time | 4-6 months | 6-9 months | 9-18 months |
This schedule assumes sufficient capacity and focus. If the project is done “on the side”, it takes longer. Large organisations often have complex dependencies that slow the process down.
How can you reduce ISO 27001 costs?
Start with a limited scope
You do not have to certify your whole organisation at once. Start with a limited scope, for example only your SaaS platform or your consultancy services. This lowers the initial costs and complexity. You can expand later.
Note that the scope must be logical and credible. A scope that covers only “the marketing department” while you are an IT company will raise questions.
Combine with ISO 9001
If you already hold ISO 9001 certification, you have a head start. Both standards follow the same structure (High Level Structure ). This means you can reuse many elements: management review, internal audit, document control and corrective actions.
Combined audits are also cheaper than separate audits. Discuss this with your certification body.
Do what you can yourself
External consultants are valuable, but you can save costs by doing work yourself. The risk assessment, writing procedures and carrying out the internal audit are tasks you can take on internally, provided you have the knowledge.
Many sources are available for free. The NCSC (Dutch National Cyber Security Centre) publishes practical guidance on information security. The CIS Controls are freely accessible and provide a good basis for technical measures.
Compare certification bodies
Request quotes from several bodies. Prices can differ significantly, as can their approach and their experience in your sector. Some bodies have specialisations. A body with a lot of experience in the IT sector will understand your environment more quickly.
Also pay attention to the reputation and attitude of the auditor. A constructive auditor who thinks along with you is more valuable than a cheap auditor who only ticks boxes.
Is ISO 27001 worth the investment?
This is the question you must ask yourself. The costs are real, but the benefits can also be substantial:
Access to new markets. Many enterprise customers and government organisations require ISO 27001 from their suppliers. Without a certificate, you are not eligible for these contracts.
Lower risk. A good ISMS reduces the chance of security incidents and limits the impact if something goes wrong anyway. The costs of a serious data breach, both financial and reputational, can be many times higher than the investment in certification.
Structure and clarity. The implementation process forces you to think about your security in a systematic way. Many organisations discover gaps they did not know existed.
Compliance. ISO 27001 helps you meet laws and regulations such as the AVG (the Dutch name for GDPR) and sector-specific requirements.
For organisations that work with sensitive information, or that provide services to customers who take security seriously, ISO 27001 is often not a luxury but a necessary investment.
More information
- ISO 27001 step-by-step plan: from start to certificate
- Requirements of the standard: what does ISO 27001 require exactly?
- The audit process: what can you expect?
- ISO 27001 for SaaS companies: costs and approach specific to software companies
- Frequently asked questions: answers to practical questions