Kirsten Munn — Fractional CFO for SaaS & AI Businesses
ICAEW (ACA) · US CPA · 20 years across Big 4, international markets, and VC-backed scale-ups. Helping SaaS and AI founders build the financial infrastructure they need to scale with confidence.
Kirsten is a Fractional CFO for investor-backed SaaS and AI businesses — ICAEW (ACA) and US CPA qualified, with two decades of experience spanning Big 4 firms, international roles, and senior finance positions in PE and VC-backed scale-ups. She is the founder of SaaS Scaler.
She currently works with 3 clients ranging from pre-revenue to £6M ARR, embedding herself as a strategic finance partner. Based near Liverpool, UK, she works remotely across multiple time zones and currencies.
20
Years Experience
Across Big 4, industry, and fractional roles
£6M
Max Client ARR
Current client ARR range: £0K–£6M
3
Big 4 Firms
EY, KPMG, Deloitte — rigour at the core
What I Do
I embed myself in your business as your Fractional CFO — typically one or two dedicated days per week — working alongside your existing team to bring strategic financial leadership without the cost of a full-time hire.
My clients are typically SaaS and AI businesses with up to £10M ARR that are scaling internationally and need someone who understands subscription economics, investor expectations, and the operational reality of building a business.
Services
SaaS Reporting
P&L restructuring and consolidated reporting across multi-entity, multi-currency businesses.
Financial Modelling
Budgets, reforecasts, and scenario planning in Excel and Fathom.
Board & Investor Packs
The numbers, narratives, and slides that go to your board and investors.
SaaS Metrics
ARR, MRR, GRR, NRR, LTV, CAC, and unit economics — calculated and reported correctly.
Fundraise Readiness
Numbers, story, and data room in shape before you go to market.
Systems Implementation
Xero, NetSuite, AccountsIQ, chart of accounts design, and process automation.
My Career Journey
1
EY Tokyo
Started in Big 4 tax — working across UK, US, and Japanese tax in my early twenties.
2
Into Industry
Moved into senior finance roles at PE and VC-backed SaaS scale-ups.
3
KPMG & Deloitte
Continued Big 4 career, building deep technical rigour across international tax and compliance.
4
SaaS Scaler
Founded SaaS Scaler — bringing Big 4 rigour and hands-on scaling experience to fractional clients.
That combination — Big 4 rigour, international experience, and hands-on scaling work — is what I bring to every client engagement.
Credentials & Deep Expertise
Qualifications
ICAEW (ACA) — Chartered Accountancy
US CPA — Certified Public Accountant
Advanced Financial Modelling — Financial Modelling Institute
International Tax & Transfer Pricing — UK, US, and Japan
Accounting Standards — UK GAAP, US GAAP, and IFRS
Financial Modelling & Forecasting — advanced Excel and Fathom
Investor Relations & Fundraise Prep — data rooms and investor-ready numbers
Multi-Entity Consolidation — across currencies and accounting systems
How I Work — Part of Your Team, Not a Consultant Who Disappears
I'm not a consultant who sends a report and disappears. I become part of your team. I have dedicated days for each client, join your Slack, attend your board meetings, and work directly in your systems.
Dedicated Days
One or two dedicated days per week — focused, consistent, and deeply embedded in your business.
3–4 Clients at a Time
Focused enough to go deep, broad enough to bring pattern recognition from across the SaaS landscape.
What Moves Things Forward
Clean reporting. Clear metrics. Confident decisions. That's what good finance infrastructure gives you.
SaaS Metrics I Work With Every Day
Understanding the right metrics — and calculating them correctly — is the foundation of investor-ready SaaS finance. Here's the core framework I apply across every client engagement.
ARR / MRR
Annual & Monthly Recurring Revenue — the heartbeat of your SaaS business.
GRR / NRR
Gross & Net Revenue Retention — the clearest signal of product-market fit and expansion.
LTV / CAC
Lifetime Value vs. Customer Acquisition Cost — the unit economics that determine scalability.
CAC Payback
How long it takes to recover acquisition costs — critical for cash flow planning.
Beyond Client Work
Liverpool & North West Tech Community
Actively attending events and building relationships with founders and investors across the Liverpool and North West UK startup ecosystem.
AI in Finance — Early Adopter, Healthy Sceptic
I use Claude for research, analysis, and writing support — but maintain healthy scepticism about where AI adds genuine value. The best finance leaders will use AI as a tool, not a replacement for rigorous thinking.
Ideal Client
Is This You?
My clients are SaaS and AI founders who are past the early chaos and starting to scale — but who don't yet have the financial infrastructure to match their ambitions.
1
Up to £10M ARR
You've found product-market fit and you're growing — but your finance function hasn't kept pace with the business.
2
Scaling Internationally
You're operating across multiple currencies, entities, or jurisdictions and need someone who's done this before.
3
Investor-Backed or Fundraise-Ready
You have investors to report to, or you're preparing to raise — and you need your numbers to tell a compelling, credible story.
4
Ready for a Finance Partner, Not Just a Bookkeeper
You want someone who sits at the leadership table, challenges assumptions, and helps you make better decisions with your numbers.
Get in Touch
Let's Talk About Your Business
If you're a SaaS or AI founder with revenue up to £10M ARR and you need strategic finance leadership, I'd love to hear about your business. Book an intro call to see if we're a good fit.
Book an Intro Call
A no-pressure conversation to understand your business and see if there's a fit.
Connect on LinkedIn
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