What is a Fractional CISO and How Can It Help European B2B Companies?

Many European B2B companies make a costly mistake by attempting to hire a full-time CISO before they are adequately prepared.

After 13 years of building security programs for Forbes Cloud 100 companies, banks, and B2B scale-ups, I've reviewed 150+ security programs. The pattern is clear: most growing companies need strategic security leadership, but hiring a full-time CISO too early can kill momentum and drain resources.

Here is what works best.

The Full-Time CISO Problem Nobody Talks About

For B2B companies with €5-50M in revenue, hiring a full-time CISO is often not the best choice.

This is because hiring a full-time CISO costs €150-250K per year, plus equity, benefits, and a lengthy hiring process, for someone who may spend much of their time on tasks that are not yet needed. Most companies at this stage do not have a mature enough security program to require full-time strategic leadership.

I've seen CTOs burn out trying to handle security between product sprints. 

I've watched founders lose €20M deals because they couldn't answer basic security questionnaires. 

And I've seen companies hire expensive CISOs who leave within 18 months because there wasn't enough scope for them to make a meaningful impact.

The primary issue is that European B2B companies must meet enterprise-level security requirements, but often lack the same resources as large enterprises.

What is a Fractional CISO?

A fractional CISO (Chief Information Security Officer) is a senior security executive who works with multiple companies on a part-time, strategic basis. Think of it as having a battle-tested security leader available for 1-3 days per week, rather than five.

However, not all fractional CISOs offer the same level of expertise or service.

Many security consultants have never built a complete security program. They may audit your current state, produce a lengthy report that is never implemented, and then move on. This approach is costly and does not provide real value.

A true fractional CISO goes beyond giving advice. They help build your security program, guide you through ISO 27001 audits, improve your responses to vendor questionnaires, present to your board, and make security decisions that support business growth.

Why European B2B Companies Need Different Security Leadership

European B2B companies encounter challenges that are not covered by typical American approaches:

Regulatory complexity, including the GDPR, NIS2, sector-specific requirements, and multiple jurisdictions, creates compliance burdens that American companies don't face. Your customers in Germany have different security expectations than those in the Netherlands or the UK.

European enterprises typically demand ISO 27001 or equivalent certifications before initiating procurement conversations. In the US, many deals close without certifications. In Europe, no certification often means no conversation.

European B2B companies typically have smaller teams and tighter budgets compared to their US counterparts at the same revenue stage. You can't throw money at the problem; you need smart, efficient security programs.

Operating across EU member states means navigating different data residency requirements, local regulations, and varying security maturity expectations from customers.

I've navigated M&A transactions worth over €150M, supported deals with the world’s largest and most highly regulated organizations, and built security programs that helped scale from €10M to over €100M in revenue. The companies that succeed don't copy Silicon Valley playbooks; they build pragmatic security programs that fit European market realities.

The Real ROI: What Fractional CISO Services Actually Deliver

The most important factor is the impact on revenue.

Deals that close: Enterprise procurement committees require evidence of security maturity. When you can demonstrate a functioning security program, answer questionnaires confidently, and provide ISO 27001 or SOC 2 certification, deals that would have stalled for 6-12 months close in weeks.

I've watched sales teams lose €5-20M opportunities because "security maturity is insufficient." Then, I watched those same companies close identical deals 90 days after implementing proper security governance.

The difference? They could finally answer the questions enterprise buyers actually ask.

Investor confidence: Series B investors now mandate security diligence. A fractional CISO provides the strategic oversight that satisfies investors without the full-time cost. In my experience, companies with clear security leadership receive better valuations and smoother due diligence processes.

Cost optimization: A fractional CISO working 2 days per week costs anywhere between €10,000 and €14,000/month. A full-time CISO costs €17-20K+/month in salary alone, plus 3-6 months to hire, plus equity, plus benefits. You save 40-70% while getting 13+ years of proven experience starting immediately.

But here's the real ROI nobody calculates: the opportunity cost of getting security wrong. Every week without a demonstrable security capability costs you €200-500K in stalled pipeline. Competitors with mature security stories are winning the deals you pioneered.

A Quick note

Is security blocking your next enterprise deal?

Let's discuss how fractional CISO services can unlock your pipeline without the full-time overhead.

Book a Free Discovery Call

How Fractional CISO Services Work (The Honest Version)

Most consultants will promise you the world in a glossy PDF and call themselves advisors without touching anything. However, most consultants are wrong because that’s not a service but rather an AI-generated output.

I'm going to explain exactly how pragmatic and customer-driven fractional CISOs work and what you can expect. Here is how we approach it at Mandos:

Phase 1 (Weeks 0-4): Rapid Assessment. We assess your current security posture, identify immediate risks, and prioritize based on business impact. You get a clear roadmap of what needs fixing and why. No 200-page reports; just actionable priorities tied to your revenue goals.

Phase 2 (Months 2-6): Enterprise-Ready Security. We build your security program alongside your technical teams. This means implementing controls, documenting policies, establishing governance processes, and preparing for compliance certifications. The goal is to pass enterprise security reviews and close deals.

Phase 3 (Months 4-8): Certification. Navigate ISO 27001 or SOC 2 audits with minimal disruption to your team. We manage auditor relationships, evidence collection, and remediation. Our track record: 100% first-time pass rate on audits.

Phase 4 (Month 7+): Ongoing Governance. Once certified, you require continuous leadership, including board reporting, program maturity, regulatory adaptation, and strategic decision-making. This is where fractional CISO services deliver long-term value: ongoing executive oversight without full-time cost.

What this isn't:

• Not a security audit that produces reports nobody implements
• Not a compliance checkbox exercise that doesn't improve actual security
• Not vendor-agnostic consulting that recommends €500K tool stacks
• Not someone who disappears after the PowerPoint presentation

What this is: Real security leadership that makes decisions, implements solutions, and drives business outcomes.

The Three Critical Use Cases for Fractional CISO Services

After working with dozens of B2B companies, three scenarios consistently drive the need for fractional CISO services:

1. Deal-Driven Security Requirements

Your sales team is in late-stage negotiations with an enterprise customer. Procurement sends a 300-question security assessment. Your CTO doesn't have time to answer it, and your team doesn't know how to proceed.

This is the most common trigger. Enterprise customers now require evidence of security maturity before signing contracts. If you can't demonstrate a functioning security program, the deal dies, regardless of how good your product is.

A fractional CISO responds to RFPs, manages enterprise security conversations, and provides the documentation that procurement committees demand. The goal is to remove security as a blocker to revenue.

2. Compliance Certifications (ISO 27001, SOC 2, NIS2)

Investors mandate compliance frameworks. Enterprise contracts require certifications. Regulations impose penalties for non-compliance.

But Big 4 consultants quote €150K+ and 18-month timelines. Your 25-person team is already at capacity. Pulling engineers away from product development to build compliance programs can kill momentum.

A fractional CISO implements lean, business-focused compliance programs that satisfy auditors without enterprise overhead. I achieved ISO 27001 and SOC 2 certifications within 6-8 months, with 100% first-time pass rates, because the goal is certification that enables business, not security theater.

3. M&A Security Integration

You're acquiring a company or being acquired. Security due diligence reveals gaps. Integration requires consolidating security programs, tools, and teams to achieve a comprehensive security approach.

I've conducted security assessments for dozens of mergers and acquisitions (M&A) transactions. The companies that succeed treat security as a business enabler during M&A, not an afterthought. A fractional CISO manages due diligence, identifies risks, and leads post-merger integration without derailing the deal timeline.

What to Look for in a Fractional CISO (Red Flags and Green Flags)

The security consulting market is rife with individuals selling snake oil. Here's how to tell the difference between real expertise and expensive PowerPoints:

Red flags:

• Promises ISO 27001 certification in 6 weeks (impossible)
• Leads with tool recommendations before understanding your business
• Uses fear-based selling ("You'll get breached tomorrow!")
• Can't explain complex security concepts in simple business terms
• Has never built a complete security program from scratch
• Focuses on compliance theater instead of business outcomes

Green flags:

• Battle-tested experience building security programs at scale
• Clear track record of audit success (not just consulting work)
• Can explain security ROI in business terms, not technical jargon
• Understands European regulatory requirements (GDPR, NIS2, sector-specific)
• Has navigated M&A security due diligence
• Focuses on pragmatic solutions that fit your growth stage

Here's my bias: I've built security programs for Forbes Cloud 100 FinTech companies, navigated over €150M in M&A transactions, and achieved 100% first-time pass rates on ISO 27001 and SOC 2 audits. I understand what enterprise buyers demand because I've helped companies close deals with the world’s largest and most highly regulated organizations.

However, these credentials don't matter if the approach doesn't align with your company's needs. The right fractional CISO understands your business context, aligns security with revenue goals, and builds programs that scale with your growth, not against it.

A Quick note

Is security blocking your next enterprise deal?

Let's discuss how fractional CISO services can unlock your pipeline without the full-time overhead.

Book a Free Discovery Call

The Investment: What Fractional CISO Services Actually Cost

Let me give you the numbers consultants usually hide until the third meeting.

Full-time CISO cost:

• Salary: €150-250K annually (€12.5-20.8K/month)
• Benefits, equity, taxes: +30-40%
• Recruitment fees: €30-50K
• Time to hire and onboard: 4-6 months
• Risk of wrong hire: High (18-month average tenure if mismatched)

Total first-year cost: €200-350K+, with 6 months before productivity

Fractional CISO costs, on the other hand, range from €10,000 to €14,000/month depending on the engagement scope, region, and time commitment. Most engagements are structured as monthly retainers rather than hourly billing, providing predictable costs and strategic continuity. (At least that’s how we prefer to deliver maximum value to customers here at Mandos.)

In exchange, you get immediate productivity, 40-70% cost savings, and a proven track record. The investment pays for itself when you close the first enterprise deal that was previously blocked by security concerns.

When Should You Actually Hire a Full-Time CISO?

Here's the honest answer: when you have the scope and resources to justify one.

Consider a full-time CISO when:

• Revenue exceeds €100M with a mature security program already established.
• You have a security team of three or more people who require daily leadership.
• You're operating in multiple regions with complex compliance obligations.
• Board members and investors specifically mandate full-time security leadership.

Stick with a fractional CISO when:

• Revenue is €10-100M M and the security program is still being built.
• The CTO is handling security reactively, balancing it with product priorities.
• You need enterprise security capability but not full-time overhead.
• Compliance certifications are driving the immediate need.
• You're navigating mergers and acquisitions (M&A) or a major transformation.
• You want flexibility.

The mistake most companies make? Hiring a full-time CISO too early, burning cash on someone who doesn't have enough scope, then watching them leave within 18 months. Or waiting too long, losing deals to competitors with better security maturity.

Fractional CISO services bridge that gap, providing strategic leadership when you need it most, at a cost structure that fits your growth stage.

FAQ: Fractional CISO Services for European B2B Companies

What is a fractional CISO, and how is it different from a security consultant?

A fractional CISO is a senior security executive who works with your company on a regular, part-time basis (typically 1-3 days per week). Unlike consultants who audit and advise, a fractional CISO executes, building security programs, making strategic decisions, managing audits, and providing ongoing leadership and guidance. Think of it as having an experienced CISO on your executive team without the full-time cost.

What is the cost of a fractional CISO in Europe?

Fractional CISO services typically range from €10,000 to €14,000/month, depending on the engagement level (1-3 days per week). This represents 40-70% savings compared to hiring a full-time CISO (€150-250K annually plus benefits, equity, and recruitment costs). The investment pays for itself when you close enterprise deals that were previously blocked by security requirements.

How long does it take to get ISO 27001 or SOC 2 certified with a fractional CISO?

With a pragmatic, business-focused approach, ISO 27001 or SOC 2 certification typically takes 6-8 months from start to successful audit completion. This timeline assumes reasonable starting maturity and dedicated internal resources to implement controls. Companies with strong technical teams can achieve certification faster; those with limited capacity may take longer. Beware of consultants promising 6-week certifications, they're selling fantasy.

Can a fractional CISO work remotely, or must they be on-site?

Most fractional CISO work is conducted remotely with periodic on-site visits for key activities (audit preparation, board presentations, major incidents). For European B2B companies, this model works well: you get experienced leadership without geographic limitations. Critical situations (major security incidents, audit weeks) may require on-site presence, but day-to-day strategic work happens effectively remotely.

What's the difference between a fractional CISO and a vCISO?

These terms are often used interchangeably, but there's a subtle distinction: "fractional CISO" typically implies a senior executive working with a limited number of clients (3-5 companies), providing deep engagement and strategic leadership. "vCISO" (virtual CISO) sometimes refers to lower-touch, more distributed consulting models. The key question: Is this person making executive-level security decisions for your company, or just providing advice?

How do I know if my B2B company needs a fractional CISO?

You need fractional CISO services if: (1) Enterprise customers are asking security questions you can't answer confidently, (2) You're pursuing ISO 27001 or SOC 2 certification, (3) Investors are demanding security maturity, (4) Your CTO is drowning in security work, or (5) You're navigating M&A that requires security due diligence. If security has become a blocker to revenue, it's time for strategic leadership.

What industries benefit most from fractional CISO services?

B2B SaaS, FinTech, data platforms, enterprise software, enterprise AI, and any technology company selling to enterprise customers benefit most from fractional CISO services. These companies face stringent security requirements from buyers, yet they operate with lean teams and tight budgets. Industries with strong regulatory requirements (financial services, healthcare, critical infrastructure) also benefit, though may eventually need full-time security leadership as they scale.

How many companies does a fractional CISO typically work with?

An effective fractional CISO typically works with 3-5 companies simultaneously, dedicating 1-3 days per week to each client. This balance ensures deep engagement and strategic impact while maintaining cost efficiency. Beware of "fractional CISOs" working with 10+ companies; they're spreading themselves too thin to provide meaningful leadership.

Can a fractional CISO help with NIS2 compliance for European companies?

Yes. NIS2 (Network and Information Security Directive 2) applies to many European B2B companies, particularly those in critical sectors or providing digital services. A fractional CISO can assess your NIS2 obligations, implement required security measures, establish governance processes, and ensure ongoing compliance. This is increasingly important as EU member states enforce NIS2 requirements with serious penalties for non-compliance.

What happens during a typical fractional CISO engagement?

A typical engagement follows four phases: (1) Rapid assessment of your current security posture and business priorities (weeks 0-4), (2) Building enterprise-ready security program and preparing for certifications (months 2-6), (3) Navigating audits and achieving ISO 27001/SOC 2 certification (months 4-8), and (4) Ongoing governance, board reporting, and continuous program maturity (month 7+). The timeline adjusts based on your immediate needs and existing maturity.

How do I measure ROI on fractional CISO services?

ROI shows up in three ways: (1) Revenue impact - enterprise deals that close faster because you can demonstrate security maturity, (2) Cost avoidance - not hiring a full-time CISO saves €100-200K+ annually while getting proven expertise immediately, and (3) Risk reduction - avoiding compliance penalties, data breaches, and reputational damage. Most companies see positive ROI within the first 90 days when security stops blocking enterprise sales.

What's the typical contract length for fractional CISO services?

Initial engagements typically run 6-12 months to build and certify a complete security program. After achieving initial goals (certification, enterprise readiness, compliance), many companies continue with ongoing governance at reduced time commitment (1 day/week). The goal is to build a security capability that eventually becomes self-sustaining, rather than creating a permanent dependency.

The Bottom Line on Fractional CISO Services

European B2B companies face a fundamental challenge: enterprise customers demand security maturity, but they lack the necessary enterprise resources.

Fractional CISO services solve this problem - providing battle-tested security leadership when you need it most, at a cost structure that fits your growth stage.

After 13 years of building security programs and reviewing over 150 B2B companies, I've learned what actually works: pragmatic security programs that unlock revenue, simplified compliance that satisfies auditors, and strategic leadership that scales with business growth.

The companies winning enterprise deals in 2025 aren't outspending competitors; they're out-executing them with smart security strategies.

If security is blocking your next enterprise deal, delaying your fundraising, or consuming your technical team's bandwidth, it's time to talk.

Book a complimentary 30-minute discovery call to explore whether fractional CISO services are a suitable fit for your organization. No sales pitch, just an honest conversation about your security challenges and whether I can help solve them.

Nikoloz Kokhreidze
Fractional CISO | Founder at Mandos
13+ years turning security roadblocks into competitive advantages

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