Fractional CFO vs Full-Time CFO
A complete comparison to help UK founders decide which finance leadership model fits their stage and their runway.
Quick answer
Choose a fractional CFO if: you are pre-seed to Series A, you need investor-ready financials and a model you can defend, and you would rather spend runway on the product than on a six-figure salary.
Choose a full-time CFO if: you have a finance team to lead, your board has made it a condition of the round, or the job genuinely fills a week.
Side-by-side comparison
Figures are UK market ranges for 2026, not a price list. What an engagement costs depends on your stage and the intensity you need.
| Factor | Fractional CFO | Full-Time CFO |
|---|---|---|
| Year-one cost | £24,000-£144,000 | £210,000-£360,000 |
| Equity dilution | None | 0.5-2% |
| Time to start | 1-2 weeks | 3-6 months |
| Weekly availability | 8-16 hours | 40+ hours |
| Commitment | Monthly, 30-day notice typical | Permanent employment |
| Exit cost if it fails | Notice period | Severance plus a repeat search |
| Day-to-day presence | Scheduled days and fundraise spikes | In the room every day |
| Typical fit | Pre-seed to Series A | Series B and beyond |
The real cost breakdown
A salary is the visible part of a full-time hire. Employer National Insurance, pension, benefits and the recruiter's fee land in the same year, and the seat usually sits empty for three to six months while you search.
Fractional CFO
- Monthly retainer£2,000-£12,000
- Employer NI£0
- Pension contribution£0
- Benefits£0
- Recruitment fees£0
- Equity0%
- Year-one total£24,000-£144,000
Full-Time CFO
- Base salary£150,000-£250,000
- Employer NI£18,000-£30,000
- Pension£5,000-£10,000
- Benefits£5,000-£15,000
- Recruitment fees£30,000-£60,000
- Equity0.5-2%
- Year-one total£210,000-£360,000
At a typical seed-stage engagement of £3,500 a month, the year-one difference runs to well over £150,000, before counting the equity and the months the seat stands empty. For the full picture, read how much a fractional CFO costs in the UK.
When to choose each option
Choose a fractional CFO when:
- You are pre-seed to Series A
- You need investor-ready numbers before a raise
- Runway is under 18 months and every fixed cost matters
- Your finance work spikes around raises and board meetings
- You want senior judgement without committing equity
- You need someone in place in weeks
Choose a full-time CFO when:
- You are post-Series B with a finance team to lead
- Regulatory reporting demands a named, permanent officer
- Your model runs on daily commercial decisions at volume
- Investors or your board have made it a condition
- You need 40+ hours a week of finance leadership
- The role is as much people management as financial judgement
What the fractional model gives up
Availability between scheduled days
A fractional CFO is contactable, but they are not sitting in your standup. If your week turns on finance decisions taken hourly, that gap will show.
Line management depth
Two or three days a week can lead a small finance function. Building and managing a team of eight is a full-time job, and pricing it fractionally is the expensive way to get one.
Permanence in the eyes of a regulator
Some regulated activities expect a named officer with a permanent contract. Check your obligations before assuming a fractional appointment satisfies them.
Weighing an outsourced provider instead? Read Fractional CFO vs Outsourced Finance Function. Working out when you need the role at all? Try the free Startup Runway Calculator.
Financial Leadership
Still not sure which is right for you?
Request a free 30-minute call. We will help you assess your stage and say so if a fractional CFO is the wrong answer.