What a fractional CFO does
A fractional CFO is a senior finance executive you hire part-time — a few days a month instead of a full-time salary. They own the forward-looking side of your finances: cash-flow forecasting, financial modeling, fundraising prep, pricing and margin analysis, and the numbers behind big decisions like hiring or opening a location.
This is not bookkeeping or tax filing. A bookkeeper records what happened; an accountant reports and files on it; a fractional CFO tells you what the numbers mean and what to do next. Many small businesses have all three, and the CFO sits on top, working from the reports the others produce. For the boundary between the two senior roles, see fractional CFO vs accountant.
Unlike a controller, the CFO isn’t focused on day-to-day accounting operations — they’re focused on strategy and the story your finances tell investors, lenders, and you.
What it costs
Fractional CFO retainers typically run $3,000 to $12,000 per month. A few days a month of oversight for a stable business sits at the low end; heavy involvement during a fundraise or a turnaround, with weekly modeling and board prep, sits at the top. Three things move the price:
- Time commitment — a one-day-a-month advisory retainer costs far less than three days a week.
- Stage and complexity — fundraising, multiple entities, or inventory-heavy operations demand more senior hours.
- Experience — a CFO who has raised a Series A or sold a company in your industry commands a premium, and usually earns it.
See the full breakdown in our fractional CFO cost guide.
How to evaluate one
Ask for specifics. A real fractional CFO can name a client whose runway they extended, whose margins they fixed, or whose raise they closed — with numbers. Vague talk about “strategic guidance” is a warning sign. Confirm they’ll do the work personally rather than passing it to a junior financial analyst while charging CFO rates.
A strong engagement starts with a diagnostic: they read your books, build or rebuild a model, and come back with a short list of what’s broken and what it’s worth to fix. An amateur jumps straight to a long retainer without that groundwork. Make sure the scope names deliverables and a monthly hour band, so “out of scope” doesn’t become a surprise invoice.
When you don’t need one
Most businesses under roughly $1M in revenue don’t need a CFO yet — a solid bookkeeper plus a good accountant covers the ground, and you can lean on a financial planner for personal decisions. The value appears when the money decisions get big and irreversible: raising capital, pricing a new line, deciding whether you can afford to hire five people. Bring in a fractional CFO when a wrong call would cost more than the retainer — and none of this replaces advice from a licensed professional on your specific situation.
Questions to ask before you hire
- Which companies at my stage and revenue have you worked with, and what changed under you?
- Will you do the work yourself, or hand it to a junior analyst on your team?
- How many hours or days a month does the retainer cover, and what falls outside it?
- Do you build the financial model and forecast, or only review what my bookkeeper produces?
- What's your exit plan — how do you hand off to a full-time hire when I'm ready?
Red flags
- They can't point to a specific metric or decision they improved at a past client.
- The retainer is vague about hours, deliverables, or what counts as extra.
- They pitch a long lock-in contract before understanding your finances.
- They conflate the role with bookkeeping or basic accounting — that's not what you're paying for.