Fractional vs Full-time Finance Director

Growing UK SMEs eventually hit a wall where the founder, an outsourced accountant or a financial controller can no longer carry the weight of board-level finance. At that point owners face a clear decision: hire a full-time finance director at £100k–£180k plus benefits, or engage a fractional finance director services provider for the days the business genuinely needs. The right answer is rarely about prestige and almost always about economics, capability and timing. This guide breaks the decision down across cost, capability, speed, flexibility and organisational fit, then gives you a five-question framework to reach a confident, defensible conclusion for your own business.

What does a Finance Director actually do?

A finance director is not a senior accountant. The role sits at the executive table and owns the commercial and strategic side of finance. That means shaping the three-year plan, pressure-testing the operating model, modelling pricing and margin decisions, leading banking and investor conversations, preparing the organisation for an exit, and translating numbers into board-ready narrative.

Contrast that with the rest of the finance team. A bookkeeper processes transactions. A management accountant produces the monthly numbers. A financial controller owns compliance, controls and the finance team’s day-to-day output. All three are essential, but none of them are paid or trained to challenge the CEO on capital allocation, negotiate with a private equity acquirer, potential trade sale, or rebuild the commercial model before a funding round. That is FD territory — and it is the single most commercially valuable seat in the finance function. Getting it right, or wrong, compounds across every other decision the business makes.

Cost comparison: the real numbers

The headline salary for a full-time FD is only the starting point. Once you layer in employer NI, pension, benefits, bonus, recruitment fees and the opportunity cost of a three-to-six-month ramp-up, the true year-one cost is materially higher than the offer letter suggests.

Cost component	Full-time FD (year one)
Base salary	£140,000
Employer NI (approx. 15%)	£21,000
Pension contribution (5%)	£7,000
Benefits, healthcare plan, bonus, car allowance	£15,000
Recruitment fee (20% of salary)	£28,000
Ramp-up / opportunity cost	~£15,000
Total year-one cost	~£226,000

Even if you strip out recruitment and ramp-up — which you only avoid if you already have the right person in your network — the fully-loaded cost still lands around £183k against a £140k offer letter. That gap is the number most owners miss.

A fractional engagement carries none of those add-ons. There is no employer NI, no pension contribution, no benefits package, no recruitment fee and no ramp-up, because you are engaging someone who already does the job elsewhere. You pay for the days the business actually uses, and the commitment moves with you — up around a funding round or a sale, back down when the pressure eases. Ending an engagement is a conversation rather than a redundancy process, which is a structural advantage rather than a rounding error.

What that adds up to depends entirely on how much genuine FD work your business has. That is worth establishing honestly before comparing any numbers, and the five questions at the end of this guide are a good place to start.

Capability comparison

A full-time FD brings depth. They live inside your P&L, know every customer and every supplier. That proximity matters — especially for operational decisions that need daily context. But depth has a cost. A single full-time FD gives you exactly one perspective, shaped by their previous businesses they have worked with and their other clients.

A fractional FD brings breadth. Most senior fractional practitioners have 20 to 30 years of experience across 20+ different businesses — PE-backed, founder-led, SaaS, services, manufacturing, pre-exit, post-acquisition. When your business hits a problem, they have almost certainly seen it solved a number of different ways at different companies, and they can tell you which approach actually worked. That pattern recognition is very hard to hire permanently at SME salary levels, because the people who have it tend to be operating as portfolio FDs by choice.

For most £1m–£15m businesses, breadth of experience delivers a higher return than pure depth — especially during growth, exit planning or investor-facing phases.

Speed comparison

Hiring a full-time FD is slow. A realistic timeline looks like this: 4 to 6 weeks to brief a search firm and define the role, 6 to 10 weeks to interview a shortlist, 2 to 4 weeks to negotiate an offer, and then 3 months of notice period before they even start. Add onboarding and you are typically 6 to 9 months from “we need an FD” to “our FD is fully productive”.

A fractional FD compresses that timeline dramatically. Most engagements start within 2 to 4 weeks of the first call. Because the individual is already an experienced FD operating across multiple clients, there is no onboarding curve in the traditional sense — they are producing board-ready output, running cash flow management improvements and tightening management reporting inside the first month. For a business facing a funding round, a cash crunch, or a fast-moving acquisition conversation, that speed difference is not a convenience — it is the difference between seizing the opportunity and missing it.

When is a full-time FD actually the right call?

There are clear scenarios where a full-time FD is genuinely the better decision. The most obvious is scale: once turnover is comfortably above £15m and you already have a finance team of six or more people, the FD needs to be present daily to lead that team, set priorities, coach the controller and own the rhythm of the function.

Second, decision velocity. If your business makes material commercial decisions several times a week — large bids, M&A discussions, complex pricing calls, daily treasury moves — a fractional FD who is on site periodically may create bottlenecks. The finance function needs a permanent seat at the table.

Third, regulated industries. FCA-regulated firms, insurers and certain healthcare or defence-adjacent businesses genuinely require a named, on-site senior finance officer for regulatory and insurance reasons. In those cases, the decision is made for you.

When is fractional the right call?

Fractional is the right answer for the vast majority of UK SMEs between £1m and £10m in turnover. At that scale, a full-time FD is usually underutilised — the business simply does not have 5 days a week of genuine FD-level work. Paying £180k fully loaded for 2 days of strategic output and 3 days of “finding something useful to do” is one of the most common — and expensive — mistakes scale-up CEOs make.

Fractional is particularly powerful during specific phases. Rapid growth, where the operating model needs constant rework and the investor conversation is live. Exit planning, where what you need is someone who has been through five or six M&A transactions, not someone who has been through one. Funding rounds, where the model, the data room and the investor narrative need to be built from scratch in 60 days. Post-acquisition integration, where finance processes have to be harmonised quickly. And cost-conscious scale-ups where every £10k of overhead has to earn its place.

In all of those situations, a fractional FD delivers more strategic output per pound than a full-time hire, while leaving you the flexibility to scale the engagement up or down as the business evolves. Read more on why fractional works for owner-managed businesses.

Decision framework: 5 questions

Use these five questions to reach a clear answer for your own business — most founders overestimate how much FD work they genuinely have.

1. How much genuine FD work does the business actually have? Not finance work generally — that is a controller or management accountant’s job. Specifically board-level, strategic, commercially-facing FD work. Most founders overestimate it. If there is a full week of it every week, a permanent hire starts to make sense. If it concentrates around month-end, board meetings and the occasional big decision, fractional is almost certainly the right call.

2. Is your finance function already mature, or still being built? If you have a clean close, reliable monthly management accounts, a working forecast and a capable controller, you need a part-time strategist on top. If your finance function is still being built from scratch, you probably need a hands-on fractional FD to design and install it — then step back.

3. Are you 12 to 24 months from a major event? An exit, an investment round, a major acquisition or a refinancing. If yes, fractional experience across many similar events beats single-business depth almost every time.

4. What is your realistic budget ceiling for finance leadership? If it is £100k or less fully loaded, a full-time FD at the level you actually need is not realistic. Fractional is the only way to buy genuine senior experience at that price point.

5. Have you tried fractional first? A 3-to-6-month fractional engagement is one of the lowest-risk ways to understand exactly what your business needs from an FD before you commit to a six-figure permanent hire. Many businesses discover they never needed full-time after all.

What Oppenheim Advisory offers

Oppenheim Advisory provides experienced, board-level fractional finance director services to ambitious UK SMEs. Engagements are flexible — a few hours across the week or a couple of days a month, scaling up around a funding round or a sale and back down afterwards — and cover strategic planning, cash flow, management reporting, funding preparation and exit readiness. You get senior FD experience at a cost that fits a £2m–£10m business, without the recruitment risk, notice period or fully-loaded salary of a permanent hire. If you are weighing this decision right now, contact us for a free consultation — we will give you a straight answer on whether fractional is right for your business, even if the answer is no.