Accretion / Dilution Analysis
Think of accretion/dilution as the EPS litmus test for a deal — does buying this company make our earnings per share go up (accretive, good) or down (dilutive, bad)? It's the first thing public company boards ask about.
Definition
Accretion/dilution analysis determines whether a proposed acquisition will increase (accrete) or decrease (dilute) the acquirer's pro forma earnings per share (EPS). A deal is accretive if pro forma EPS exceeds the acquirer's standalone EPS, and dilutive if it falls below.
Formula
Pro Forma EPS = (Acquirer Net Income + Target Net Income - After-Tax Financing Costs + After-Tax Synergies) / Pro Forma Diluted Shares Accretion/Dilution = Pro Forma EPS - Acquirer Standalone EPS % Accretion/Dilution = (Pro Forma EPS / Standalone EPS) - 1
Accretion / Dilution Math
Does the deal increase or decrease EPS?
Accretive
+8.3%
EPS increases from $3.00 to $3.25
Accretive vs. Dilutive
The key question: does target yield exceed financing cost?
Target's earnings yield exceeds the cost of financing the deal — every dollar spent earns more than it costs.
Cost of financing exceeds target's earnings yield — paying more to fund the deal than you get in earnings.
Financing Matters
Same deal, different financing — different EPS impact
+6.0%
Accretive
Key insight: Accretive if target's after-tax earnings yield > after-tax interest rate on cash
How the Analysis Works
Step 1: Calculate the acquirer's standalone EPS (Net Income / Diluted Shares). Step 2: Calculate the target's contribution to combined earnings (target Net Income, adjusted for deal financing costs and synergies). Step 3: Calculate new share count (acquirer's shares + any new shares issued to pay for the deal). Step 4: Pro Forma EPS = Combined Net Income / New Diluted Share Count. If Pro Forma EPS > Standalone EPS, the deal is accretive. The analysis is performed for Years 1, 2, and 3 post-close.
Key Drivers of Accretion/Dilution
Financing mix: using cash or debt (lower cost) is more accretive than issuing equity (which increases share count). Purchase price: a higher premium increases dilution. Relative P/E ratios: if the acquirer's P/E is higher than the target's, a stock deal is naturally accretive (you're buying cheaper earnings). Cost synergies: expense savings flow directly to combined net income, improving accretion. Revenue synergies are typically not included because they are harder to achieve and less credible to investors.
The P/E Rule of Thumb
In an all-stock deal: if the acquirer's P/E > target's P/E, the deal is accretive. If the acquirer's P/E < target's P/E, the deal is dilutive. Why? A high-P/E acquirer issues fewer shares (its stock is 'expensive') to buy a low-P/E target (the target's earnings are 'cheap'). This rule is a quick shortcut but doesn't account for synergies, financing mix, or transaction costs. Always build the full model for precision.
Why Accretion/Dilution Matters
Public company acquirers are sensitive to EPS dilution because it can pressure their stock price. Most boards will not approve a deal that is dilutive beyond Year 1 without a compelling strategic rationale and clear path to accretion. Investment banks present accretion/dilution analysis in every merger model pitch book to address this concern. However, accretion/dilution alone does not determine whether a deal creates value — a dilutive deal with strong NPV may still be the right move, and an accretive deal at an inflated enterprise value can destroy value.
Worked Example — With Real Numbers
Acquirer: $500M Net Income, 100M shares, EPS = $5.00. Target: $80M Net Income, acquired for $1.2B funded 50% cash (at 5% pre-tax cost) and 50% stock (20M new shares at $30/share). After-tax interest cost = $600M × 5% × (1-25%) = $22.5M. Cost synergies = $30M pre-tax = $22.5M after-tax. Combined NI = $500M + $80M - $22.5M + $22.5M = $580M. Pro Forma EPS = $580M / 120M = $4.83. Dilution = $4.83 - $5.00 = -$0.17 or -3.3%. [Goodwill](https://www.ibflash.com/concepts/goodwill) would also be created on the acquirer's balance sheet.
Key Takeaways
Accretive = pro forma EPS goes up, dilutive = pro forma EPS goes down compared to acquirer standalone
The P/E shortcut: in an all-stock deal, if the acquirer's P/E > target's P/E, the deal is naturally accretive
Cash/debt financing is more accretive than stock because it doesn't increase the share count
Cost synergies improve accretion by adding to combined net income — revenue synergies are usually excluded from base cases
Accretion/dilution alone doesn't determine if a deal creates value — a dilutive deal with strong NPV may still be worth doing
Common Mistakes in Interviews
Saying a dilutive deal is automatically bad — strategic acquisitions may be dilutive in Year 1 but create long-term value
Forgetting to include after-tax financing costs when modeling a cash or debt deal
Not adjusting for new shares issued in a stock deal — the denominator changes, which is the whole point
Confusing accretion/dilution with value creation — an accretive deal at an inflated price can still destroy shareholder value
How Interviewers Test This
This is a staple M&A interview question. Know: 'Is this deal accretive or dilutive and why?' Walk through the drivers. The shortcut: 'In an all-stock deal, if the acquirer's P/E is higher, the deal is accretive.' But always caveat that synergies and financing costs affect the result. Practice the full calculation with numbers — interviewers expect you to work through it on the spot.
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