What Is a Fractional CFO — and When Does Your Startup Actually Need One?

A full-time CFO at a growth-stage company commands $250,000 to $450,000 a year in total compensation. For most companies under $20M in revenue, that is not just expensive — it is premature. The strategic work a CFO does at that stage rarely fills forty hours a week. What fills the week is everything else: closing the books, chasing invoices, running payroll. Work that should not cost CFO dollars.

A fractional CFO solves that mismatch. You get a seasoned finance executive for a defined slice of time — typically a few hours a week — focused exclusively on the decisions that move the business, while the operational layer underneath is handled by accountants, automation, or both.

What a fractional CFO actually does

• Cash flow forecasting and scenario planning — knowing your runway under a base case, a downside case, and a hiring plan before you commit to any of them.
• Pricing strategy — modeling how a price change flows through to margin, churn, and runway.
• Board and investor preparation — packages that answer questions before they are asked.
• Budget design — departmental budgets that give managers autonomy without giving away the runway.
• Fundraise and diligence readiness — clean data rooms, defensible models, and numbers that tie out.

Five signals you need one

1. You make hiring or spending decisions without knowing how they change your runway.
2. Board meetings take a week of scramble to prepare for.
3. You have revenue but no idea which products, projects, or customers are profitable.
4. You are six to twelve months from raising, and your books would not survive diligence.
5. Your accountant reports what happened, but nobody tells you what to do next.

What it should cost

Standalone fractional CFO engagements typically run $3,000 to $10,000 per month depending on complexity. The more efficient model — the one we run at Silken — bundles CFO advisory with the underlying accounting operation, so the strategist works from books that are already clean, current, and automated. Bundled engagements start around $1,500 per month, because AI handles the mechanical layer that traditionally inflated the bill.

The point of a fractional CFO is not fewer hours of finance. It is more decision-making per dollar of finance spend.

If any of the five signals above sound familiar, the math almost always favors starting now: the cost of six months of unmanaged burn nearly always exceeds a year of fractional CFO fees.