Fractional CFO vs Full-Time CFO in the UK: The Real Cost Difference

When a business reaches the point where it needs serious financial leadership, the instinct is often to hire a full-time CFO. It feels like the grown-up move. But in the UK, that decision carries a cost that most founders and CEOs significantly underestimate and comparing a fractional CFO vs full-time CFO properly means looking well beyond the headline salary figure.

This article breaks down the real numbers: what a full-time CFO actually costs a UK employer once you account for salary, employer National Insurance, pension contributions, benefits, and recruitment fees. Then it sets that against what a fractional CFO typically costs, and what you actually get for each.

If you are weighing up your options and want to make a genuinely informed decision, this is the comparison you need.
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What a Full-Time CFO Actually Costs in the UK

The salary range for a full-time CFO in the UK sits between £190,000 and £300,000 per year, depending on sector, company size, and location (Robert Walters, 2024). For a London-based CFO at a scale-up or mid-market business, the upper end of that range is common. But salary is only the starting point.

From April 2025, employer National Insurance sits at 15%, with the secondary threshold lowered to £5,000 (HMRC, 2025/26). On a £220,000 salary, that adds roughly £32,250 in NI contributions alone. Add mandatory auto-enrolment pension contributions, typically 3% to 5% at the employer level for senior hires, and you are adding another £6,600 to £11,000 per year.

Then there are the less visible costs. Private health insurance for a senior executive typically runs £2,000 to £5,000 per year. Life assurance, income protection, and a company car or car allowance are standard at this level. A performance bonus of 20% to 30% of base salary is common. Add these together and a CFO on a £220,000 base salary costs an employer closer to £290,000 to £320,000 per year in total cash and benefits.

That figure does not include recruitment. Executive search fees for a CFO typically run at 20% to 30% of first-year salary, meaning a £44,000 to £66,000 one-off cost before the person has started. If the hire does not work out within the first 12 months — which happens more often than most businesses plan for — that cost is absorbed with little recourse.

For a detailed breakdown of on-costs by market, see the Fractionus UK cost guide.

What a Fractional CFO Costs in the UK

A fractional CFO works with your business on a part-time or project basis, typically under a monthly retainer. In the UK, that retainer generally ranges from £5,000 to £14,000 per month, depending on the scope of work, the seniority of the individual, and the number of days engaged per month.

Most engagements sit in the range of one to three days per week. A two-day-per-week fractional CFO at the mid-range of the market might cost £8,000 to £10,000 per month, or £96,000 to £120,000 per year. That is the total cost. There is no employer NI on a contractor arrangement, no pension obligation, no benefits package, no recruitment fee, and no notice period or redundancy
liability.

The engagement can typically be scaled up or down as the business needs change. If you are heading into a fundraise, a merger, or a period of financial restructuring, you can increase the hours. If things stabilise, you can reduce them. That flexibility has real financial value that does not appear in a simple cost comparison.

It is worth noting that the fractional model is not simply about cost reduction. The executives who operate fractionally are typically senior professionals who have held full-time CFO roles and choose to work across multiple businesses simultaneously. Understanding what fractional work actually means helps clarify why the quality of output is not diminished by the part-time structure.

Side-by-Side: The Numbers That Matter

To make this comparison concrete, consider a UK business with £15M in annual revenue that needs a CFO to lead financial reporting, support a Series B raise, and build out the finance function over 18 months.

Full-time CFO (estimated 18-month cost)

→ Employer NI at 15%: approximately £48,375

→ Pension (4% employer): approximately £13,200

→ Benefits (health, life, car allowance): approximately £15,000

→ Performance bonus (20%): approximately £66,000

→ Recruitment fee (25% of salary): approximately £55,000

→ Total estimated cost: £527,575

Fractional CFO (estimated 18-month cost)

→ 18 months total: £162,000

→ No NI, no pension, no benefits, no recruitment fee

→ Total estimated cost: £162,000

The difference in this scenario is over £365,000. Even if the fractional retainer were higher — say £12,000 per month — the 18-month total would be £216,000, still less than half the full-time cost.

These are illustrative figures based on typical market rates. Your actual costs will vary depending on the individual, the scope, and your specific circumstances. But the structural gap between the two models is consistent.

When a Full-Time CFO Is the Right Choice

There are situations where a full-time CFO is genuinely the better option, and it is worth being honest about that.

If your business has revenue above £50M to £75M and the finance function involves daily management of a large team, complex treasury operations, board-level reporting across multiple entities, and ongoing investor relations, the volume and complexity of the work may genuinely require someone present five days a week. At that scale, the cost of a full-time CFO is more easily justified.

Similarly, if your business is preparing for a significant public market event — an IPO or a large institutional fundraise — there is an argument for a full-time CFO who is entirely focused on your business during that process. The reputational and legal stakes are high, and some investors and advisors will expect to see a full-time finance leader on the cap table.

Culture fit and internal leadership can also be a factor. If you need someone who will manage a large finance team day-to-day, drive organisational change, and sit in the business for extended periods, a fractional arrangement may not provide enough presence to do that well.

The honest answer is that most businesses under £30M in revenue do not need a CFO present five days a week. They need one present for the right conversations, at the right moments — and a fractional structure delivers exactly that.

What to Look for When Hiring a Fractional CFO in the UK

Not all fractional CFOs are equal, and the quality of the market varies considerably. Some executives operating fractionally are genuinely exceptional: former Big Four partners, CFOs of listed companies, or operators who have taken businesses through significant transactions. Others are less experienced professionals using the fractional label to fill gaps between permanent roles.

The difference matters. A fractional CFO who has never personally managed a fundraise, navigated an acquisition, or built a finance function from scratch will struggle to add value at the level you are paying for. Vetting is everything.

When evaluating candidates, look for:

→ Evidence of outcomes, not just responsibilities held

→ References from previous fractional or full-time CFO roles

→ Clarity on how they structure their time across multiple clients

→ A track record of working with businesses at your revenue stage

Fractionus accepts fewer than 3% of executive applicants onto the platform. Every CFO in our network has been assessed against a structured vetting process — you can read more about how we vet talent if you want to understand what that involves.

The Hidden Costs That Rarely Get Counted

Beyond the direct financial comparison, there are several costs associated with full-time hiring that rarely appear in a spreadsheet but are very real.

Time to hire is one. A senior CFO search in the UK typically takes three to six months from briefing to start date. During that period, your business is either operating without financial leadership or paying an interim at day rates that can exceed £1,500 to £2,500 per day. A fractional CFO can typically be in place within days, not months.

Mis-hire risk is another. A CFO who joins full-time and does not work out — whether due to culture, capability, or a change in business direction — costs far more than the recruitment fee. There is the opportunity cost of the months spent managing a poor fit, the disruption to the finance team, and the cost of starting the search again. Fractional engagements carry a much lower risk profile: if the fit is not right, the engagement ends cleanly.

Finally, there is the cost of over-hiring. A business at £10M revenue that hires a full-time CFO at £220,000 per year is paying for a level of capacity and seniority it may not need for another two to three years. That money could be deployed elsewhere — in product, sales, or operations — while a fractional CFO covers the strategic finance work the business actually needs right now.

Understanding the full picture of fractional executive costs and structures helps businesses make decisions based on real economics, not assumptions.

If you are ready to find a vetted fractional CFO for your UK business, submit your brief at Fractionus and receive a shortlist of qualified candidates within two to five days. No recruitment fees. No lengthy search process. Just the right person, available when you need them.

Frequently Asked Questions

What does a fractional CFO cost in the UK?

A fractional CFO in the UK typically costs between £5,000 and £14,000 per month on a retainer basis, depending on the scope of work and days engaged per month. This is the total cost to your business — there is no employer NI, pension, benefits, or recruitment fee on top.

What is the average CFO salary in the UK?

Full-time CFO salaries in the UK range from £190,000 to £300,000 per year in base salary, depending on company size, sector, and location (Robert Walters, 2024). Once employer NI at 15% (HMRC, 2025/26), pension, and benefits are added, the true employer cost is typically £250,000 to £420,000 per year.

Is a fractional CFO a contractor or an employee?

In most UK arrangements, a fractional CFO operates as an independent contractor or through their own limited company. This means the business does not carry employer NI obligations, pension contributions, or employment law protections in the same way as a permanent hire. You should always take appropriate IR35 advice for your specific situation.

How many hours per week does a fractional CFO typically work?

Most fractional CFO engagements in the UK involve one to three days per week, though this varies based on the business's needs. Engagements can be structured around specific projects, such as a fundraise or financial system build, or as an ongoing strategic retainer across the financial year.

When should a business hire a full-time CFO instead?

A full-time CFO is typically warranted when a business exceeds £50M to £75M in revenue, has a large internal finance team requiring daily management, or is undertaking a public market event such as an IPO. Below that threshold, most businesses are paying for capacity they do not yet need.

How quickly can I get a fractional CFO through Fractionus?

Fractionus delivers a shortlist of vetted fractional CFO candidates within two to five business days of receiving your brief. This compares with a typical executive search process that can take three to six months for a permanent hire. You can learn more about how we vet our executives before you submit your brief.

Does a fractional CFO work across multiple businesses at the same time?

Yes. Most fractional CFOs work with two to four businesses simultaneously. This is a feature of the model, not a limitation — it means you access an executive whose experience spans multiple sectors and situations, rather than someone whose perspective is shaped by a single organisation.

Is fractional CFO hiring common in the UK?

It is growing significantly. The global fractional executive market was valued at $5.7 billion in 2024, growing at 14% annually (Frak Conference, 2024). In the UK, the model is particularly well established in the scale-up and private equity-backed business community, where cost discipline and flexibility are priorities.