Fractional, full time or interim CFO: which model fits your SME or startup

Past a certain point, the finance function of an SME or startup no longer fits in the owner’s spreadsheet and the accountant’s annual filings. Decisions get denser: bank negotiations, cash forecasting, budgeting, pricing, sometimes a fundraise or a sale. Three formats then give you access to real CFO capacity: the fractional CFO, the full time CFO and the interim CFO. Same profession in all three cases. But not the same commitment, not the same cost, not the same use case. I have seen owners pay for the wrong format for two years straight; the error quickly adds up to tens of thousands of euros a year.

Three models, three different logics

On paper, the skill set is comparable in all three cases: an experienced finance director who can talk to a bank, build a forecast and sharpen the owner’s decisions. What really changes is the format of the engagement. How often the person shows up, for how long, and above all how easily you can reverse course if the need shifts.

• The fractional CFO: a senior finance director who works one to four days a month, on an ongoing basis. This person sets up monthly steering, cash forecasting and the bank relationship, and remains the owner’s permanent finance counterpart. Commitment: months to years, adjustable and quick to stop.
• The full time CFO: a salaried executive, present five days a week. The right format when the volume of financial decisions genuinely fills a calendar: a finance team to manage, several entities, structured financing, demanding reporting to shareholders or a group. Commitment: a hire, with probation, notice period, onboarding and a fixed cost.
• The interim CFO: a senior profile deployed at high intensity, often four or five days a week, for a defined period of three to nine months. Built for exceptional situations: a sudden CFO departure, a cash crisis, a fundraise, a sale, integrating an acquisition. Commitment: an assignment, with a start, an end and a precise objective.

What each model really costs

Comparing headline rates is misleading, because the three models are not billed in the same unit. A daily rate, an annual salary, a monthly retainer: none of these compare directly. The only honest comparison is the full annual cost, set against what it buys.

• Full time: for an experienced profile in France, expect between €130,000 and €200,000 a year in full employer cost (salary, social charges, bonus, tools, recruiting cost). That cost is fixed whether the calendar is full or not, and it recurs every year.
• Fractional: depending on intensity, most engagements run between €2,000 and €8,000 a month, or €24,000 to €96,000 a year. The format scales up or down with the season: denser during the budget or a bank negotiation, lighter in steady state.
• Interim: daily fees for an interim manager often sit between €900 and €1,500. At full intensity, an assignment costs €20,000 to €30,000 a month. It is the most expensive format per month, and rightly so: you pay for immediate availability, seniority and intensity, over a short period.

The right model is not the cheapest of the three. It is the one whose format matches the real density of financial decisions to be made.

The decision grid by size and situation

Two questions settle most cases. How many structural financial decisions does your company face each month? And is your situation normal growth or an exceptional event? Size gives the first indication; the situation corrects it.

• Below €2M of revenue, stable situation: a good accounting firm and a weekly cash sheet are often enough. A fractional CFO can step in lightly, one day a month, to set up the steering and prepare bank deadlines.
• From €2M to €10M: the natural zone for the fractional model. There is enough complexity to justify a real finance director, not enough volume to fill a full time role. One to three days a month cover the monthly close, the forecast, the bank and the owner’s key calls.
• From €10M to €30M: the full time question becomes serious, especially with a finance team to manage, several entities or structured debt. A frequent and effective combination: an internal finance manager for the daily work, plus a fractional CFO for the strategic layer.
• Exceptional event, at any size: an unplanned CFO departure, an acute cash crisis, a sale or an acquisition in progress. An intensified fractional engagement or an interim assignment takes over for the duration of the event, then the format steps back down.

A worked example: a services SME at €5M

Among our clients, the typical case looks like this: a services SME at €5M of revenue, 35 employees, €500,000 of EBITDA. The owner hesitates between hiring a full time CFO, around €160,000 in full annual cost, and a fractional CFO at two days a month, around €4,000 a month or €48,000 a year. Take the inventory of the year’s financial decisions: it fits in a few lines. One budget, twelve monthly closes, two bank negotiations, one pricing overhaul. None of these tasks requires daily presence. All of them require seniority. The fractional format covers the need, and the difference, roughly €110,000 a year, funds a senior salesperson or stays in the bank. The full time hire becomes relevant again around €15M to €20M, when the finance team has three or four people to manage and the calendar is genuinely full.

The common mistakes when choosing

• Hiring full time too early: the role is expensive, the calendar never fills, and the CFO ends up doing bookkeeping at €150,000 a year. Frustration on both sides, a departure after 18 months, and the cost of the failed hire lands on top.
• Confusing accounting and financial leadership: the first produces compliant accounts and looks backward, the second sharpens decisions and looks forward. The two roles are complementary; neither replaces the other.
• Choosing on the daily rate rather than annual cost and outcome: an advisor at €1,200 a day, two days a month with a clear mandate, costs less and delivers more than a €600 a day profile present every week without a roadmap.
• Covering a permanent need with an interim manager: past nine months, the assignment costs double a full time role and the knowledge leaves with the person. An interim assignment ends; it does not stretch on indefinitely.
• Taking on a fractional CFO with no framework: with no monthly rhythm and no defined deliverables (dashboard, cash forecast, monthly review with the owner), the engagement dissolves into occasional advice with no cumulative effect.

In the end the decision comes down to density: how many financial decisions your company has to make, how often, and for how long. For most SMEs and startups between €2M and €10M, the fractional model has a structural advantage I see engagement after engagement: it is reversible. You start light. You intensify during a fundraise or a bank negotiation. You switch to a full time hire the day the calendar justifies it, without having locked in €160,000 a year in the meantime. A one hour review is usually enough to establish which format your situation calls for today, and at what threshold it will tip into the next one.

Choose the continuity your decisions require

List recurring work, temporary projects and responsibilities requiring daily presence. The choice depends on workload, available data and the existing team. A transaction assignment serves a different need from monthly reviews of contribution and cash.

For annual support, agree review timing, data preparation, action tracking and how urgent decisions are handled. Compare actual scope before job titles or days of attendance.

See how to prepare this decision.

Frequently asked questions

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