The average AI business case presented to Australian CFOs in 2025 contained optimistic vendor projections, vague efficiency estimates, and no risk analysis. Most were rejected. The ones that got approved shared a common structure.
Start With the Problem, Not the Solution
CFOs are sceptical of technology-led proposals. Lead with the problem: what is the current cost, why is it growing, and why is it not being solved by existing means? Quantify it precisely — not "we spend a lot of time on invoicing" but "our AP team processes 2,400 invoices monthly at an average handling time of 8 minutes, costing $187,000 per year in labour."
The Three Numbers CFOs Need
- Total cost of status quo (annual) — fully loaded: labour, error correction, opportunity cost
- Implementation cost (one-time) — software, integration, change management, contingency (add 25%)
- Ongoing cost post-implementation (annual) — licensing, maintenance, oversight headcount
From these three numbers, payback period and 3-year NPV are straightforward. CFOs can stress-test the assumptions themselves.
Credible Assumptions Beat Optimistic Projections
Don't claim 95% automation rates from vendor case studies. Use 60-70% as your base case, 80% as upside. Show your working. CFOs approve conservative projections with clear upside more readily than aggressive projections with no supporting evidence.
Address Risk Directly
Most AI business cases ignore risk entirely. This destroys credibility. Include a risk register with three to five items, likelihood ratings, and mitigation strategies. For each risk, show the financial impact if it materialises and how the investment thesis still holds.
The Approval Structure That Works
Structure your business case in this order:
- Executive summary — problem, proposed solution, expected return, ask
- Current state — quantified cost of the problem
- Proposed solution — what it does, what it doesn't do
- Financial model — costs, savings, payback, NPV
- Risk analysis — top risks, mitigations, residual exposure
- Implementation plan — phases, timeline, resource requirements
- Decision required — specific approval sought
Keep it under 12 pages. CFOs read executive summaries and financial models. Everything else is supporting evidence they'll refer to if needed.
One More Thing
Get a reference. One Australian business of comparable size that has implemented the same solution and can speak to actual results — not projected ones — is worth more than any analysis you can produce internally. If your vendor can't provide one, that's a risk worth noting.