Fractional CFO vs full-time CFO: which fits your stage?
Cost, scope & ramp compared.
A side-by-side comparison: fractional CFO vs full-time CFO for UK SaaS startups. Cost, scope, time commitment, equity dilution and ramp time — so you can pick the right model for your stage.
Side-by-side
How the two options compare.
| Fractional CFO | Full-time CFO | |
|---|---|---|
| Typical UK cost | £30k–£96k/yr | £180k–£250k/yr all-in |
| Equity | None | 0.5%–2% |
| Time to start | 2 weeks | 3–6 months hire + ramp |
| Notice period | 30 days either side | 3–6 months |
| SaaS specialism | Day one | Hit-or-miss |
| Capacity | 1–5 days/month | 5 days/week |
| Team-building | Partial — guides hires | Full — builds finance team |
| Board attendance | Yes | Yes |
| Risk if wrong hire | Switch in 30 days | £40k+ exit, 6 months lost |
Decision framework
Three questions to ask yourself.
If you answer no to any of these, you’re not ready for a full-time CFO yet.
1. Can you afford £200k+/yr and a finance team under them?
A full-time CFO without a finance manager, financial analyst and FP&A support underneath is wasted. The real cost is closer to £400k for the full function.
2. Do you have 5 days of CFO-level work every week?
Below £8m ARR most SaaS finance functions need a senior brain 3–8 days a month, plus a strong bookkeeper/manager. Hiring full-time too early means an expensive person doing the wrong work.
3. Will you raise Series B in the next 12 months?
Series B investors expect a full-time CFO at close. If your raise is 18+ months out, stay fractional. If it’s imminent, start the search — it takes 4–6 months.
When to switch
The signals that say it’s time for full-time.
ARR consistently above £8m
Finance complexity (multi-entity, multi-currency, revenue recognition, statutory audit) crosses the threshold where 3 days/month is no longer enough.
Series B closed or in the next 6 months
Series B+ boards expect a permanent CFO. Plan the hire to land 60–90 days post-close so the fractional CFO can handover.
M&A on the roadmap
Buy-side or sell-side M&A is full-time work for 6–18 months. Even strong fractionals can’t carry it alongside other clients.
Team of 80+ or finance team of 5+
Once you have a head of finance, FP&A and a controller, you need a CFO to lead them — not a fractional CFO advising them.
Next step
Not sure which side of the line you’re on?
20-minute call. We’ll tell you honestly — even if the answer is ‘hire full-time’.
The honest answer
When fractional wins and when full-time wins.
The honest answer depends on three variables: stage, runway sensitivity and time horizon to next major event. Run yourself through them honestly.
Stage. Below £10m ARR, full-time CFO output is usually under-utilised 2–3 days a week. The work simply isn’t there yet at the level of seniority required. Above £15m ARR, full-time becomes the right answer — there’s enough strategic finance, treasury, IR, audit and team-leadership work to fill the seat.
Runway sensitivity. If saving £150k+/yr extends runway by 4+ months and that buys you a materially better fundraise or sale outcome, fractional is the obvious answer. If cash isn’t a constraint, the comparison becomes about time-to-hire and ramp, which still typically favour fractional for sub-£10m businesses.
Time horizon to next major event. If you’re 18–24 months from a sale or IPO, hiring a permanent CFO who’ll exit at the event is expensive (recruitment, ramp, severance). Fractional through the event with a hand-over to a permanent CFO post-close is often the cleaner shape.
Side-by-side
Fractional CFO vs full-time CFO — direct comparison.
Six dimensions that matter for the decision. No spin — both have a place; pick the one that fits your situation.
Cost (year 1, all-in)
Fractional: £30k–£96k. Full-time UK: £180k–£250k base + benefits + recruitment fees.
Equity dilution
Fractional: 0%. Full-time: typically 0.5%–2%, often the largest line item in comp.
Time-to-hire
Fractional: 2 weeks to embedded. Full-time: 3–6 months via search + 30–90 day notice period.
Ramp time
Fractional: productive in week 2. Full-time: 6+ months to full output and credibility.
Scope flexibility
Fractional: scales up for raise, down after. Full-time: fixed cost regardless of demand.
Long-term partnership
Full-time wins above £15m ARR. Fractional wins below, and for time-bounded events.
Decision framework
A simple decision framework — five tests.
Score yourself out of five. 3+ ‘yes’ answers means fractional is almost certainly the right shape today.
Are you below £10m ARR?
Below £10m, full-time CFO output is typically under-utilised.
Is the next raise >6 months away?
If imminent, full-time loses on time-to-hire and ramp.
Is headcount below 60?
Below ~60 FTEs, finance-org volume usually doesn’t justify full-time.
Do you value optionality?
Fractional scales up and down — full-time can’t.
Is cash a constraint?
Saving £150k+/yr extends runway materially without losing senior finance.
FAQ
Questions founders ask.
What does a full-time CFO actually cost in the UK?
£150k–£200k base, 0.5–2% equity, £15k–£25k employer NI/pension/benefits, plus £30k–£50k recruiter fee. All-in first-year cost is £200k–£300k. Plus the finance team underneath.
How many days does a fractional CFO work per month?
Typically 1–5. Essential package is ~1.5 days, Growth ~3 days, Fundraise 5+ days. Day-rate engagements are 5–15 days total.
Can a fractional CFO close my Series A?
Yes — most of our fundraise clients close Series A with us, then transition to a full-time CFO 3–6 months post-close. We’ve supported 40+ rounds.
What’s the biggest mistake founders make here?
Hiring full-time too early. £200k of runway burnt on a CFO doing work a senior bookkeeper plus a fractional could cover for £80k.
Will a full-time CFO build my finance team?
Yes — that’s the main reason to hire one. They recruit and lead the controller, FP&A and finance ops layer. Fractionals can guide the hires but not own them day-to-day.
Can you help us transition to a full-time CFO later?
Yes. We’ve handed over to incoming CFOs 8+ times. Documented handover pack, two-week parallel, introductions to your board, accountants and investors.
Book a free call
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