FA-301h · Module 1

ROI, NPV, and IRR

3 min read

Three financial tools dominate investment analysis, and each answers a different question. ROI answers "how much do I get back per dollar invested?" NPV answers "what is this investment worth in today's dollars?" IRR answers "what is the effective annual return?" Using the wrong tool for the question produces a technically correct answer that is practically useless. A CFO evaluating a 3-year platform investment needs NPV, not simple ROI. A sales leader justifying a tool purchase needs ROI, not IRR.

Investment: $180,000 platform implementation
Year 1 benefit: $60,000
Year 2 benefit: $95,000
Year 3 benefit: $120,000
Discount rate: 10%
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Simple ROI:
  Total benefit: $275,000
  ROI = ($275K - $180K) / $180K = 52.8%
  → "For every dollar invested, we get $1.53 back."

NPV:
  PV of benefits: $60K/1.1 + $95K/1.21 + $120K/1.33
                = $54.5K + $78.5K + $90.2K = $223.3K
  NPV = $223.3K - $180K = $43,300
  → "This investment creates $43K in value
     above what we could earn at 10%."

IRR:
  Rate where NPV = 0 → solve for r
  IRR = 22.4%
  → "This investment earns 22.4% annually,
     which exceeds our 10% hurdle rate."
  1. Use ROI for Simple Comparisons ROI is the ratio of net benefit to cost. It is easy to calculate, easy to understand, and appropriate for short-term investments (< 12 months) where time value of money is negligible. Weakness: it ignores timing — an investment that returns 50% over 1 year is better than one that returns 50% over 5 years, but ROI treats them the same.
  2. Use NPV for Long-Term Investments NPV discounts future cash flows to present value, capturing the time cost of money. An NPV above zero means the investment creates value beyond the discount rate. NPV is the most theoretically sound method and the one CFOs trust most. It answers the only question that matters: is this investment worth more than its alternatives?
  3. Use IRR for Comparing Alternatives IRR is the discount rate that makes NPV equal to zero — it represents the investment's effective annual return. Useful for comparing projects with different scales: a $50K investment at 35% IRR may be better than a $500K investment at 18% IRR, depending on capital constraints. Weakness: IRR can produce multiple solutions for non-conventional cash flows.