Fractional CFO for SaaS & AI Founders
Common questions about fractional CFO services, SaaS finance, and working with SaaS Scaler — answered clearly.
What is a Fractional CFO?
The Simple Definition
A fractional CFO is an experienced Chief Financial Officer who works with your business on a part-time basis — typically one or two days per week — rather than as a full-time hire. You get strategic financial leadership, board-level reporting, and hands-on finance expertise at a fraction of the cost.
The Right Fit
For SaaS and AI businesses between £0.3M and £10M ARR, a fractional CFO is often the ideal solution. You need someone who understands subscription economics and investor expectations, but don't yet have the budget or need for a full-time hire.
How is it Different from an Accountant or Bookkeeper?
Bookkeeper
Records transactions and keeps your books up to date. Tells you what happened.
Accountant
Handles compliance — tax returns, statutory accounts, and regulatory filings. Makes sure it's compliant.
Fractional CFO
Works at a strategic level: modelling, forecasting, board reporting, SaaS metrics, and fundraise prep. Tells you what it means and what to do next.
"Your bookkeeper tells you what happened, your accountant makes sure it's compliant, and your fractional CFO tells you what it means and what to do next."
When Should a SaaS Startup Hire a Fractional CFO?
Most SaaS businesses benefit from a fractional CFO once they reach £0.3M to £0.5M ARR and face decisions about scaling, fundraising, or international expansion.
Fundraising Round
You're preparing for a funding round and need your numbers, forecasts, and data room in shape.
Sophisticated Reporting
Your board or investors are asking for more sophisticated reporting than your bookkeeper can provide.
International Expansion
You're expanding internationally and need to understand multi-entity structures, transfer pricing, and cross-border tax.
Unit Economics Clarity
You're growing fast but don't have clear visibility on unit economics, cash runway, or profitability by segment.
Financial Infrastructure
You need someone to build the financial infrastructure that will support your next stage of growth.
If you're spending your time as a founder trying to build board packs, reconcile metrics, or figure out your runway — that's a strong signal it's time to bring in a fractional CFO.
Can a Fractional CFO Help with Fundraising?
Yes. Fundraise preparation is one of the most common reasons SaaS founders bring in a fractional CFO. Having a qualified, experienced CFO alongside you during the fundraise process significantly strengthens your credibility with investors. Each of these steps is handled end-to-end, ensuring your business is presented in the most compelling and credible light possible.
Financial Model
Build model with clear assumptions
SaaS Metrics
Calculate ARR, MRR, GRR, NRR, LTV, CAC
Due Diligence
Support Q&A and provide financial detail
Stress-Test
Validate forecasts and unit economics
Investor Reporting
Prepare clean, investor-ready data room
Working with SaaS Scaler
What Does the Engagement Look Like?
SaaS Scaler embeds directly into your business as a core part of your team, with one or two dedicated days per week. This includes joining your Slack, working in your accounting and reporting systems, attending board meetings, and working alongside your existing finance team.
Engagements begin with foundations — cleaning up reporting and building a SaaS P&L structure — before moving to growth: 5-year forecasts, cohort analysis, KPI dashboards, and strategic finance work.
Who Does SaaS Scaler Work With?
Investor-backed SaaS and AI businesses between £0.3M and £10M ARR scaling internationally. Clients are typically:
- VC or PE-backed
- Operating across multiple currencies and jurisdictions
- Facing the specific financial challenges of subscription businesses
Currently working with 3 clients ranging from £200K ARR to £6M ARR.
About Kirsten Munn
SaaS Scaler is led by Kirsten Munn, a highly qualified finance professional with deep expertise in SaaS and AI businesses.
ICAEW (ACA)
Chartered accountancy qualification from the Institute of Chartered Accountants in England and Wales.
US CPA
Certified Public Accountant qualification, enabling cross-border financial expertise across UK and US markets.
Advanced Financial Modelling
Certification from the Financial Modelling Institute — the gold standard for financial model construction.
20 Years' Experience
Big 4 training at EY, KPMG, and Deloitte. International roles in Tokyo and the US. Senior finance positions in PE and VC-backed SaaS scale-ups.
SaaS Metrics You Should Be Tracking
The right metrics depend on your stage and what decisions you're making. A fractional CFO can help you identify which metrics matter most and ensure they're calculated consistently and reported clearly.
What is a SaaS P&L and Why Does It Matter?
What is it?
A SaaS P&L restructures your management accounts to reflect how a subscription business actually works. Instead of a generic income statement, it:
- Separates revenue by type — recurring vs. non-recurring
- Groups costs by function — cost of revenue, sales and marketing, R&D, and G&A
- Calculates key margins like gross margin and operating margin
Why Does It Matter?
Investor Expectations: Investors, board members, and potential acquirers expect to see your financials in this format. It signals financial maturity and credibility.
Profitability Clarity: It gives you much clearer visibility into what's driving your profitability and where to invest for maximum return.
How Much Does a Fractional CFO Cost?
Fractional CFO fees vary based on scope, complexity, and time commitment. The key comparison point is against a full-time CFO hire.
Full-Time CFO
£150K – £250K+ per year including benefits and equity. A significant overhead for a business up to £10M ARR.
Fractional CFO
Significantly less than a full-time hire, while delivering senior-level strategic finance expertise tailored to your stage.
The best way to understand pricing for your specific situation is to book an intro call. You'll get a clear picture of what the engagement would look like.
How Do I Get Started?
It's straightforward. Here's what happens when you reach out:
01
Book a 30-Minute Intro Call
No commitment required. Just a conversation about your business.
02
Discuss Your Situation
We'll talk about where you are now and what financial infrastructure you need to reach the next stage.
03
Receive a Tailored Proposal
If there's a good fit, you'll receive a clear proposal with milestones and expected outcomes.
Ready to Scale with Confidence?
SaaS Scaler works with investor-backed SaaS and AI founders who are serious about building the financial infrastructure to support their next stage of growth. If you have up to £10M ARR and are facing decisions about fundraising, international expansion, or scaling — let's talk.
Strategic Finance
Board reporting, financial modelling, and SaaS metrics that give you and your investors full confidence.
Fundraise Ready
Data rooms, investor-ready forecasts, and a qualified CFO by your side throughout the process.
International Scale
Multi-entity structures, transfer pricing, and cross-border tax expertise for global SaaS businesses.