ISO 27001 Certification/Audit Costs in the UK (2026) - Full Breakdown

This guide explains ISO 27001 certification costs in the UK, including pricing structure, influencing factors, audit stages, and cost-saving options.

However, it’s important to note that these costs are just for the audit piece (certification), and do not factor in the additional cost that companies might need to incur on the implementation work, either from paying a consultant or a platform (or both) to prepare themselves.

Key takeaways

  • ISO 27001 certification in the UK typically costs £4,000–£20,000+, mainly driven by headcount, scope, complexity, and regulated audit duration requirements.

  • Certification follows a 3-year cycle, including Stage 1, Stage 2, annual surveillance, and recertification, making it a structured ongoing commitment.

  • Choosing UKAS-accredited, remote-first audits improves credibility, reduces procurement risk, and helps control long-term ISO 27001 certification costs.

How much does ISO 27001 certification cost in the UK?

If you are planning for ISO 27001, cost is usually the first serious question.

The ISO 27001 certification cost in the UK typically ranges from £4,000 to £15,000+ (excluding VAT) when using a UKAS-accredited certification body, depending on your organisation’s size, complexity, scope, and certification approach. 

At Tempo Audits, typical certification benchmarks are:

  • Startups (1–10 staff): £4,000 + VAT

  • SMEs (around 30 staff): £7,000 + VAT

  • Larger organisations (100+ staff): £10,000 + VAT

Surveillance audits apply annually and vary by size. The right figure depends on your structure, risk profile, and readiness - which we break down in this guide.

What is included in the ISO 27001 certification cost?

Understanding the ISO 27001 cost breakdown helps you see where your budget is allocated. 

Certification is not a single event. It follows a structured 3-year cycle, governed by ISO 27006 rules on audit duration. 

Below is what is typically included in ISO 27001 certification fees.

Stage 1 - Documentation readiness review

Stage 1 is a structured review of your ISMS documentation and preparedness.

This includes audit planning, reviewing policies and procedures, confirming scope, and assessing readiness for Stage 2. 

Audit days vary by headcount. A 1-10-person company typically involves 3-4 audit days in total, of which 1 day will be for the Stage 1, while a 100-person organisation may require 7–9 days, of which 2 to 2.25 might be for the Stage 1.

Fees cover preparation, evidence gathering, reporting, and identification of any gaps requiring correction before progressing.

Stage 2 - Full ISMS assessment

Stage 2 is the formal certification audit.

Auditors gather objective evidence to confirm your ISMS operates effectively in practice. This includes interviews, sampling records, testing controls, and reviewing your Statement of Applicability.

The fee includes audit delivery, production of the Stage 2 report, review and closure of non-conformities, final technical review, and certificate issuance.

Once successfully completed, certification is granted.

Surveillance Audits (Annual)

ISO 27001 certification cost per year includes surveillance audits.

These audits take place annually in Years 2 and 3 of the cycle. The purpose is to confirm your ISMS remains effective and compliant.

Costs vary by size. For example:

  • Startups (1-10 staff): £1,850 + VAT per year

  • SMEs (~30 staff): £3,150 + VAT per year

  • Larger organisations (~100 staff): £4,500 + VAT per year

Remote audits may reduce travel costs and operational disruption.

Recertification (Every 3 years)

ISO 27001 certification is valid for 3 years. At the end of that cycle, a recertification audit is required to continue holding the certificate.

This audit is more detailed than a surveillance audit and reassesses your full ISMS to confirm it remains effective and compliant.

The ISO 27001 certification renewal cost is mainly driven by headcount. Audit duration is regulated under ISO 27006, meaning larger teams require more audit days. 

Before renewal, the certification body will review changes such as staff growth, new locations, or expanded scope. Based on this, a revised 3-year fee structure is agreed for the next cycle.

Key factors that influence ISO 27001 certification cost

Several practical factors shape the ISO 27001 certification cost for a company. 

Most cost differences are not arbitrary. They are driven by audit time, scope, and organisational structure.

1. Company size & complexity

The starting point is team size. As team size increases, the number of required audit days increases accordingly using a table provided in ISO 27006.

Complexity then increases or decreases the number of days provided in ISO 27006. The kind of factors that increase audit length are: number of sites, risk/sensitivity of the information being held by the company (e.g. a health company or a bank is higher-risk than a pure SaaS company), dependencies on outsourcing and suppliers and maturity of the ISMS.

A straightforward SaaS startup will usually cost less to audit than a multi-site financial services firm of the same size.

More audit days directly increase certification fees.

2. Implementation method - in-house vs consultant

Your preparation approach affects total spend.

Some organisations build their ISMS internally. This can reduce upfront consultancy costs but may extend timelines if the team lacks ISO 27001 experience.

Others use consultants to accelerate readiness and reduce the risk of non-conformities during Stage 2. 

While consultancy adds cost, it can prevent delays, re-audits, and internal disruption. The right route depends on internal expertise and available time.

3. Certification body fees

Certification bodies set their own pricing structures.

Fees typically include audit planning, Stage 1 and Stage 2 delivery, reporting, non-conformity review, technical sign-off, and certificate issuance. 

UKAS-accredited bodies follow consistent audit standards, but pricing may vary slightly based on experience, sector knowledge, and service model.

When comparing ISO 27001 certification pricing, ensure you understand what is included. Feel free to book a call with our CEO, Rob Hall, if you want to understand our pricing structure.
4. Scope & number of locations

Scope has a direct impact on audit length.

If certification covers multiple offices, international branches, or several business units, auditors must review controls and evidence across each location. More sites mean more sampling and coordination, which increases audit days.

Defining scope carefully can help manage the overall ISO 27001 cost without compromising business objectives.

5. Remote vs on-site audits

Remote audits can reduce travel and accommodation expenses. While these costs are not always the largest part of the audit fee, they can represent a meaningful saving - particularly for organisations with multiple or international offices where auditors would otherwise travel to each site.

The wider benefit is operational. Remote audits reduce internal friction. They allow teams to work asynchronously, minimise disruption, and continue daily operations with less interruption. 

Over a full certification cycle, this time saving can be just as valuable as the direct financial reduction.

Reduce cost and disruption with a remote-first ISO 27001 audit

Tempo Audits offers a remote-first audit approach designed to reduce travel costs, minimise disruption, and keep the process efficient. You receive the same audit rigour and UKAS-accredited credibility, delivered in a more flexible way that fits modern teams.

Speak to Tempo Audits for a transparent, no-obligation estimate aligned to your size and scope.

How is the ISO 27001 certification cost calculated?

The main driver of ISO 27001 certification cost is audit time.

Certification bodies calculate audit duration using regulated headcount tables. As the number of employees operating under the ISMS increases, the required audit days increase. More audit days mean higher certification fees.

Scope and operational complexity also influence effort. Multiple services, higher-risk processing, or several locations can increase sampling and evidence review time.

Below is a typical audit-day and cost range model based on headcount - based on how Tempo Audits does its calculation.

Tempo Audit’s ISO 27001 audit day and cost guide

(Stage 1 + Stage 2 combined)

*These figures represent typical market ranges. Tempo Audits’ pricing is often positioned towards the lower end of the range, although final costs depend on risk profile, scope, and organisational complexity.

Please note that these cost estimates reflect Stage 1 and Stage 2 certification audit costs. Surveillance and recertification audits are calculated separately but follow the same regulated methodology.

In short, the average cost of ISO 27001 certification increases predictably with organisational size and scope.

UKAS vs non-UKAS ISO 27001 certification

Choosing between UKAS and non-UKAS certification is not simply a pricing decision. It affects credibility, acceptance, and long-term risk.

Below is a clear comparison to support informed decision-making.

Risks of non-UKAS / non-accredited certification

  • May appear lower in upfront cost, but carries additional risk

  • No independent UKAS (or other accreditation body) oversight of audit quality

  • Audit depth and rigour may vary between providers

  • Reduced scrutiny can weaken credibility with customers

  • Some clients or public sector buyers may reject the certificate

  • May require re-certification through a UKAS-accredited or other accredited certification body later

  • Can increase the overall ISO 27001 certification cost rather than reduce it

For organisations seeking long-term credibility and smoother procurement, UKAS accreditation generally provides stronger assurance and wider acceptance.

How to reduce ISO 27001 certification costs

Although audit duration is regulated under ISO 27006, there is a limited ability for certification bodies to reduce audit length and therefore cost based on the table. Here are some practical steps that can help manage your overall ISO 27001 certification cost while keeping the process efficient and controlled.

1. Use reputable consultants or platforms

To reduce audit length, and therefore cost, certification bodies need to be confident that you are well prepared, and so that they will have sufficient time to gather all the relevant evidence in a shorter audit.

The number 1 factor that gives that confidence to a certification body is if you are using a reputable consultant or platform to help you get ready. If a certification body knows that your consultant has an excellent track record in preparing companies for audit, they can be more confident that future clients of theirs (ie you!) will be equally well prepared, and can reduce the audit length accordingly.

2. Prepare an analysis of staff who are in “identical” roles

The audit length is based on the headcount primarily, but where you have large volumes of staff performing identical and repetitive tasks (e.g. if you have 48 software engineers, or 30 customer success representatives) the people in those roles can be ”square-rooted” for the sake of the headcount.

This would turn the 50 software engineers into an effective total of 7 (the square root of 48, rounded up), or the 30 customer success representatives as 6 (the square root of 30, rounded up). This approach can reduce the total headcount and allow the audit length to be reduced.
If you prepare these numbers in advance and present them to your certification body, it will support your case for a shorter audit.


3. Prepare documentation internally

The cost is calculated in proportion to the audit length, and the way that an audit length is calculated is based on the guidelines set out in ISO 27006. It effectively starts with the company size (e.g. headcount) and then reduces or increases based on risk factors.

As Tempo Audits Founder Rob Hall explains:

“Notionally, when we calculate the audit length, documentation prep isn’t a key factor - so typically documentation doesn’t have an impact on cost savings.

That said, if the client is using a system well-known to us and we know the evidence is going to be well prepared, we can use this as a factor to make a small adjustment to the audit length and therefore the price.”

In reality, the value of having documentation prepared is to make the audit a much smoother, more pleasant experience, where the auditor can gather the evidence quickly.

4. Train staff early

Audits involve interviews and evidence sampling across the organisation.

When staff understand the ISMS, their responsibilities, and key controls, the audit runs more smoothly. Clear answers reduce follow-up questions and minimise delays.

Early training also lowers the risk of non-conformities, which helps avoid additional corrective work after Stage 2.


5. Define the scope clearly

Scope has a direct impact on audit duration.

Including unnecessary services, departments, or locations increases audit days and, therefore, certification fees. A carefully defined scope ensures certification reflects genuine business need without expanding beyond what is required.

6. Use remote-first audits

Remote audits reduce travel and accommodation costs. While these are not always the largest part of the audit fee, they can create meaningful savings, particularly for organisations with multiple sites.

Tempo Audits is built to operate in remote audit environments and work with the platforms and tools our clients already use. Where appropriate, we take an agile and asynchronous approach, reviewing evidence independently when access is provided to reduce disruption. 

Got questions? We understand - check out our pre-ISO-27001-audit FAQs here.

Why ISO 27001 certification is worth it

1. Reduces risk of data breaches

ISO 27001 requires a structured Information Security Management System (ISMS). This means identifying risks, applying appropriate controls, and reviewing them regularly.

The result is not just documentation. It is a disciplined approach to protecting sensitive information, reducing the likelihood and impact of data breaches.

For many organisations, avoiding a single serious incident can outweigh the full ISO 27001 certification cost.

2. Helps win business and compliance contracts

Many enterprise clients, regulated industries, and public sector buyers expect ISO 27001 certification.

Holding a recognised certificate can shorten due diligence processes, strengthen tender submissions, and remove procurement barriers. 

In competitive markets, it is often a differentiator. Certification supports compliance positioning and commercial growth.

3. Strengthens trust with partners and customers

Trust is increasingly tied to data protection and governance.

ISO 27001 demonstrates independent verification that your information security controls are structured, monitored, and externally audited.

For customers and partners, this provides assurance that security is not informal or reactive, but embedded into how your organisation operates.

How Tempo Audits keeps certification costs transparent

At Tempo Audits, ISO 27001 costs follow a clear, predictable structure. Most organisations will see pricing broken down as follows:

For example, a 100-150-person company might pay around £10,000 for initial certification, £4,500 per year for surveillance audits, and £6,000–£8,000 for recertification in Year 3. If they choose consultancy support or software tools, that would sit within the additional ranges shown above.

Tempo keeps this structure transparent by focusing on:

  • Clear audit-day calculation based on ISO 27006 headcount rules

  • UKAS-accredited certification for recognised credibility

  • Remote-first audits to reduce travel costs and disruption

  • Encouraging strong preparation to avoid corrective delays

This ensures your ISO 27001 certification cost is predictable, regulated, and aligned to your organisation’s size and scope.

Get a clear ISO 27001 cost estimate - no surprises!

Speak to Tempo Audits for a tailored, UKAS-accredited ISO 27001 cost estimate based on your headcount, scope, and risk profile. You will receive a transparent breakdown across the full 3-year cycle, so you can budget with confidence.

FAQs

  • Most organisations complete ISO 27001 certification within 3 to 9 months. Timing depends on ISMS readiness, internal resources, complexity, and how quickly Stage 1 and Stage 2 audits are scheduled.

  • If non-conformities are identified, corrective action will be required. Minor issues rarely increase cost significantly, but major non-conformities requiring additional audit time may lead to extra fees.

  • It is a recurring commitment. Certification runs on a 3-year cycle with annual surveillance audits and a recertification audit at the end of Year 3.

  • Yes, transfer is possible. The new certification body will review your existing certificate, audit history, and ISMS status before agreeing to the transfer terms and surveillance arrangements.

  • No. Certification fees cover audit activities only. Consultancy, implementation support, software tools, or internal training are separate costs and vary depending on your chosen approach.