Your startup is growing. You need financial guidance, but you don't need (or can't afford) a full-time CFO. So you're looking for a fractional CFO. But how do you know if you're hiring the right one? Here's how to spot the good ones from the bad ones.

When You Actually Need a Fractional CFO

First, let's be clear about when you actually need a fractional CFO vs. a controller vs. a bookkeeper:

You Need a Bookkeeper If:

• You just need someone to record transactions
• Your books are simple and straightforward
• You don't need strategic guidance

You Need a Controller If:

• You need someone to manage the close process
• You need financial reporting and compliance
• You don't need strategic guidance, just operational execution

You Need a Fractional CFO If:

• You need strategic financial guidance (fundraising, tax strategy, growth decisions)
• You need financial modeling and scenario planning
• You need someone who can think strategically, not just execute
• You're preparing for fundraising or acquisition
• You need board-level reporting and analysis

What Fractional CFO Should Actually Do

A good fractional CFO does both strategic and operational work:

Strategic Work

• Financial modeling for fundraising and scenario planning
• Tax strategy research and recommendations
• Strategic guidance on growth decisions (should we hire? should we fundraise?)
• Board-level reporting and KPI frameworks
• Unit economics modeling and profitability analysis

Operational Work

• Month-end close oversight
• Financial reporting and analysis
• Process improvement recommendations
• Technical accounting guidance
• Audit preparation and management

If your fractional CFO only does one or the other, that's a problem. You need both.

Red Flags: What to Avoid

Credential-Heavy But No Startup Experience

They have a CPA, MBA, and 20 years of Big 4 experience, but they've never worked with a startup. They don't understand burn rate, runway, or what metrics actually matter for your stage. They'll give you advice that doesn't fit your situation.

Only Does Reporting

They can prepare financial statements and reports, but they can't help you understand what the numbers mean or what you should do about them. They're a bookkeeper with a fancy title, not a strategic advisor.

Can't Explain Things Clearly

If they can't explain your financials in terms you understand, that's a problem. A good CFO can translate complex financial concepts into plain English. If they're hiding behind jargon, they either don't understand it themselves or they're trying to sound smart.

No Process Improvement Focus

They're happy to do things the way you've always done them, even if it's inefficient. A good fractional CFO should be looking for ways to improve your processes, automate repetitive tasks, and make your finance function more effective.

Unclear Pricing or Scope

They're vague about what's included, how many hours they'll work, or what you'll get. A good fractional CFO should be clear about scope, pricing, and deliverables upfront.

Green Flags: What to Look For

Asks Good Questions

They want to understand your business, your goals, and your challenges before giving advice. They're not just applying a template—they're thinking about your specific situation.

Has Seen Your Stage Before

They've worked with companies at your stage (seed, Series A, etc.) and understand what you're going through. They know what metrics matter, what challenges you'll face, and what you need to prepare for.

Combines Strategy with Execution

They don't just give advice—they help you execute. They can build financial models, prepare board packets, and manage the close process. They're hands-on, not just advisory.

Focuses on Process Improvement

They're always looking for ways to make your finance function more effective. They suggest automation, process improvements, and better tools. They're not just maintaining the status quo.

Clear About Scope and Pricing

They're transparent about what's included, how many hours they'll work, and what you'll get. No surprises, no hidden fees, no vague promises.

How to Structure the Engagement

Scope

Be clear about what's included:

• Monthly financial review & board packet
• Quarterly forecasts
• Ad-hoc analysis as needed
• Strategic advisory on specific topics
• Operational support (close oversight, reporting, etc.)

Pricing

Typical fractional CFO engagements:

• $5-10k/month depending on scope
• Usually 20-40 hours/month
• Fixed monthly price (not hourly) is better for predictability
• Some firms charge hourly, which can be unpredictable

Hours

Be realistic about how many hours you need. A fractional CFO working 10 hours/month is probably not enough for most startups. 20-40 hours/month is more typical for companies that need both strategic and operational support.

Questions to Ask in Initial Conversations

•"Tell me about companies you've worked with at our stage." Do they have relevant experience?
•"How do you help companies prepare for fundraising?" Do they understand what investors need?
•"What's included in your monthly engagement?" Get specifics, not vague promises.
•"How do you help improve finance processes?" Do they focus on improvement or just maintenance?
•"Can you walk me through how you'd help us understand our unit economics?" This tests their analytical and communication skills.
•"What's your approach to financial modeling?" Do they build models themselves or just review them?

The bottom line: A good fractional CFO combines strategic thinking with operational execution. They understand your stage, ask good questions, and focus on making your finance function better—not just maintaining it. Look for someone who's done this before, can explain things clearly, and is transparent about scope and pricing.

How to Choose a Fractional CFO (Red Flags and Green Flags)