Fractional or full-time

Hiring a full-time CFO is a big milestone for a founder, but there’s no point paying £100k+ a year for someone whose work only takes up a couple of days a week. On the flipside, a founder might go fractional to save money, and end up with a finance leader who’s never available when they need them. This guide is written to help you work out what’s right for you and your business at the stage you’re at.

The maths

From my startup CFO salary page:

Full-time: £80k to £120k a year at seed and £120k to £160k at Series A, plus equity of 0.75% to 2% at seed and 0.4% to 1% at Series A.

With employer’s NI, pension, the option grant, the true cost of a Series A CFO is closer to £145k to £195k.

Fractional: £500 to £1,200 a day at seed, £700 to £1,500 at Series A.

At two days a week that’s £4,000 to £9,600 a month at seed and £5,600 to £12,000 at Series A.

Over a year, two days a week at the Series A mid-point is roughly £105,000 - and there’s no equity, NI, pension or lengthy notice period.

So fractional is cheaper but there’s a clear point where it becomes impractical. Three days a week at £1,200 a day is about £175,000 a year, and at that point you’re paying the same as a full-time Series A CFO - for someone who has other clients.

When fractional works

1. You need a CFO for a project: For example a raise, a debt facility, or restructure - if you’ve a really intense 2-3 months ahead of you, but things will settle down after then fractional could work well.

2. The strategic work is light: If you want someone to challenge the model, sit in board meetings and take the investor calls, but the day-to-day work could be managed by a Head of Finance or even outsourced, then a day a week of the right person could be exactly what you need.

3. You want to keep equity for full-time hires: A fractional CFO won’t usually qualify for EMI, because the scheme needs them working for you most of the week, so your option pool stays for the permanent team.

4. You want to test the fit: Plenty of fractional engagements turn into full-time hires. A few months working together will tell you more about how someone handles pressure and disagreement than any interview can. For the interview itself, use the executive interview scorecard.

Where it fails

1. Stock. If you’re managing fast moving inventory with cash going out in lumps and the forecast changing regularly, then a finance leader who’s only reachable one day a week isn’t that useful.

2. You want a partner. Some founders need someone to think with every day - fractional people can be excellent at the thinking but by their very definition, they’re not available for the every day.

3. Their other clients have a crisis the same week you do. It happens a lot - and no doubt there are good ones who manage it but it’s still a risk you simply don’t carry with a full-time hire.

At Apex, one of our best senior hires was fractional. He’d done the role several times before, at businesses our size, and was useful from the very first week. Senior experience at a price that a seed-stage business can afford is why I’m a believer in the model, and why I place into it.

A rough rule

If you’re under £1m in revenue and don’t handle stock then I’d recommend outsourced bookkeeping plus a fractional CFO ahead of your next raise.

Between £1m and £5m, or any stock at all, then hire a full-time Head of Finance, with a fractional CFO.

Above £5m: a full-time finance leader, and the question becomes Head of Finance or CFO.

Common questions

What is a fractional CFO?

A fractional CFO is an experienced finance leader who works part-time for several companies at once, on an ongoing basis, usually one or two days a week. It gives a startup senior help with fundraising, board reporting and cash planning before it can justify a full-time salary. Day rates for UK consumer brands typically run from £500 to £1,200 at seed and £700 to £1,500 at Series A. It’s an established model in the UK, with about a quarter of interim executives’ most recent assignments being fractional.

Sources: Suma CFO salary benchmarks; Institute of Interim Management, Interim Management Survey 2026.

Fractional CFO vs full-time CFO: how does the cost compare?

A fractional CFO at Series A typically charges £700 to £1,500 a day, so two days a week at the midpoint comes to roughly £105,000 a year, with no equity, National Insurance or pension on top. A full-time Series A CFO earns £120,000 to £160,000 base, and with employer’s NI, pension and the option grant the true cost is closer to £145,000 to £195,000. At three days a week, a £1,200 day rate is about £175,000 a year, the same as a full-time hire.

Sources: Suma, Fractional or full-time guide and CFO salary benchmarks.

Fractional CFO vs full-time CFO: what’s the difference for tax?

A full-time CFO is an employee taxed through PAYE. A fractional CFO usually invoices through their own limited company, and the off-payroll working rules (IR35) decide whether that engagement should be taxed like employment. If your company is medium or large, you’re responsible for assessing their status. If it’s small, the CFO’s own company makes that call. Fractional CFOs also rarely qualify for EMI options, which need at least 25 hours a week or 75% of their working time. Both sides should take their own tax advice.

Sources: HMRC off-payroll working (IR35) guidance; HMRC EMI manual ETASSUM53020.

For execs

If you’re a finance leader weighing up fractional work, the candidates page covers how I work on both sides.

If you’re still not sure which, a Senior Hire Review will give you a clear answer, with a salary range and a written plan.