What I Wish I Knew Before Becoming a Start-up CFO

Transitioning into the role of a CFO in a start-up is both exciting and demanding. If I could go back and give my past self some advice before making the transition from financial controller to finance leader, these are the five key insights I’d share.

1. You Don’t Have to Know Everything (and No One Expects You To)

Start-ups are fast-moving and unpredictable. New challenges arise daily, and often, neither you nor the founder has encountered them before.

The good news? That’s completely normal.

Within start-ups, you’re not just dealing with finance. You’ll be involved in fundraising, operations, commercial strategy, and team management, often tackling problems that are outside your comfort zone. The key is not to know everything but to know how to find the answers.

Here’s how:

• Leverage tools and AI – I use ChatGPT and other AI-powered platforms daily, whether for summarising reports, troubleshooting Excel formulas, or getting a framework for a policy.
• Tap into your network – Join finance leadership groups, attend events, and build relationships with other CFOs and finance professionals in start-ups. Many of them have been through the same challenges and can offer valuable advice.
• Find structured learning – My Financial Leadership Fundamentals (FLF) course exists for this exact reason. It’s a structured, hands-on approach to preparing for the CFO role. It provides practical insights, access to a strong community, and regular Q&A sessions where we tackle real-world finance leadership problems.

You don’t have to figure it all out alone—but you do need to be proactive about seeking out the right resources.

2. Future-Focused Leadership is Key

As a financial controller, you’re trained to look backwards—closing the books, reconciling accounts, and ensuring compliance. As a CFO, your mindset must shift to looking forward.

When reviewing management accounts, don’t just focus on what’s happened. Instead, ask:

• What trends are emerging?
• How can the business become more financially stable?
• How can I help the company hit its long-term strategic goals?

Your role isn’t just to report numbers but to interpret them strategically. A great CFO helps the CEO and leadership team make informed, data-driven decisions that set the business up for scalability and success.

(If you’re transitioning from financial controller to CFO, check out my blog post on making that shift—I’ll link it below.)

3. You Understand the Business Better Than Most (Even When You’re New)

Finance has one of the most unique perspectives in a business. You have full visibility over how sales, operations, marketing, and tech interconnect—often more than the department heads themselves.

Why?

• Finance sees the entire business model—how money flows in and out, what’s profitable, and what’s draining resources.
• The CFO is often the founder’s right-hand person, helping to make major strategic decisions that impact the company's future.

Your insight is incredibly valuable to the business beyond just “doing the numbers.” Learn to collaborate —engage with sales, product, and operations to ensure the financial strategy aligns with business goals.

4. Finance is a Goldmine of Insights (Use It!)

The finance function isn’t just about closing books and reconciling invoices—it’s a powerful decision-making engine.

• The data you manage tells a story—about growth, risks, and opportunities.
• Your financial reports aren’t just for the board—they can help sales, marketing, and product teams make better decisions too.
• Your insights directly impact hiring, expansion, pricing strategy, and investment decisions.

One of the biggest mistakes I see finance professionals make (and I did too!) when stepping into leadership roles is underestimating the value of their insights. Your role is to interpret the numbers so the leadership team can take action.

5. You Are Allowed (and Expected) to Challenge the Business

One of the most critical aspects of leadership is speaking up. If something doesn’t feel right, whether it’s:

• A forecast that seems too optimistic
• A budget that doesn’t align with reality
• A hiring plan that’s out of sync with cash flow

…it’s your job to ask questions and push back.

Challenging the founder (or any leadership team member) can be uncomfortable, but it’s essential. You’re there to protect the business, ensure financial discipline, and keep leadership accountable.

Finance isn’t just an internal function—it’s the foundation of every strategic decision. Founders rely on CFOs to be their trusted advisors.

Becoming a start-up CFO isn’t about knowing everything on day one. It’s about:
✅ Developing strong leadership skills
✅ Building a future-focused, strategic mindset
✅ Learning how to challenge and influence decision-making
✅ Tapping into tools, networks, and continuous learning

There are plenty of resources to help you navigate this transition, whether it’s your network, AI tools, or structured programs like the Financial Leadership Fundamentals (FLF) course.

If you’re serious about stepping up as a finance leader in the start-up world, make sure you’re investing in your own growth. You don’t have to figure this out alone—but you do have to be proactive in seeking out the right support.

Further Resources:

📌 Transitioning from Financial Controller to CFO
📌 My Latest Start-up Finance Tech Stack Recommendations
📌 Join My Next Finance Leadership Workshop