Accretion/Dilution Interview Question: How to Answer Perfectly

"Is this deal accretive or dilutive?" is a classic M&A technical question that tests whether you understand merger mechanics. It sounds complicated, but once you understand the logic, it becomes straightforward.

Here's exactly how to think about it.

What Accretion/Dilution Means

When Company A acquires Company B, the combined company has a new earnings per share (EPS).

• Accretive: The combined EPS is higher than Company A's standalone EPS
• Dilutive: The combined EPS is lower than Company A's standalone EPS

That's it. The question is simply: Does the acquisition increase or decrease EPS for the acquirer's shareholders?

The Quick Rule (Memorize This)

For all-stock deals:

If Acquirer P/E > Target P/E → Accretive If Acquirer P/E < Target P/E → Dilutive

Why this works:

P/E ratio = Price / Earnings. A higher P/E means you're "paying" with expensive currency (your highly-valued stock). If your P/E is 20x and you buy a company at 15x, you're buying earnings "cheaper" than your own, accretive.

The 60-Second Interview Answer

"To determine if a deal is accretive or dilutive, I compare the acquirer's P/E ratio to the effective P/E being paid for the target.

In an all-stock deal, if the acquirer's P/E is higher than the target's implied P/E, the deal is likely accretive because you're using expensive currency to buy cheaper earnings.

For cash deals, I compare the target's earnings yield to the after-tax cost of debt. If earnings yield exceeds the interest cost, cash deals tend to be accretive.

For mixed consideration, I'd build out the full merger model considering all sources of financing, synergies, and transaction adjustments."

Walking Through an Example

Scenario:

• Acquirer (Company A): Stock price $50, EPS $2.50 → P/E of 20x
• Target (Company B): Stock price $30, EPS $3.00 → P/E of 10x
• All-stock deal at current market prices

Analysis:

Acquirer P/E (20x) > Target P/E (10x) → Likely Accretive

Intuition: Company A is paying with stock that the market values at 20x earnings to buy a company trading at 10x earnings. The target's earnings are "cheaper" than the acquirer's, so adding them increases combined EPS.

The Full Calculation

For interviews, you should be able to walk through the actual math:

Step 1: Calculate shares issued If Company A pays $30 per share (in stock) for Company B, and Company B has 100 million shares:

• Total deal value = $30 × 100M = $3 billion
• New shares issued = $3B ÷ $50 (A's stock price) = 60 million shares

Step 2: Calculate pro forma earnings

• Company A earnings: $2.50 × 400M shares = $1,000M
• Company B earnings: $3.00 × 100M shares = $300M
• Combined earnings (before adjustments): $1,300M

Step 3: Calculate pro forma EPS

• Pro forma shares: 400M + 60M = 460M
• Pro forma EPS: $1,300M ÷ 460M = $2.83
• Standalone EPS was $2.50 → Accretive by $0.33 or 13%

What About Cash Deals?

For cash acquisitions, the analysis is different:

Compare:

• Target's earnings yield (EPS / Price = 1/P/E)
• After-tax cost of debt (Interest Rate × (1 - Tax Rate))

Rule:

• If earnings yield > after-tax cost of debt → Accretive
• If earnings yield < after-tax cost of debt → Dilutive

Example:

• Target P/E = 10x → Earnings yield = 10%
• Interest rate = 6%, tax rate = 25% → After-tax cost = 4.5%
• 10% > 4.5% → Accretive

Intuition: You're borrowing money at 4.5% (after tax) to buy earnings yielding 10%. You're earning more than you're paying.

Common Follow-Up Questions

"What about synergies?"

"Synergies improve accretion/dilution. If you achieve cost or revenue synergies, combined earnings increase, making the deal more accretive (or less dilutive). When modeling, I'd add expected synergies (usually phased in over 2-3 years) to the earnings calculation."

"What about the premium?"

"The premium affects the implied P/E you're paying for the target. If the target trades at 10x but you pay a 30% premium, you're effectively paying 13x. This makes the deal less accretive compared to paying market price."

"Why would a company do a dilutive deal?"

"Companies may accept short-term dilution for long-term strategic value. Reasons include: (1) Expected synergies that materialize over time, (2) Strategic benefits like market position, technology, or talent, (3) Blocking a competitor from acquiring the target. Management typically commits to the deal being accretive within 1-3 years once synergies are realized."

"What adjustments do you make in a merger model?"

"Key adjustments include: (1) New interest expense if using debt, (2) Lost interest income on cash used, (3) New shares issued if using stock, (4) D&A from asset write-ups, (5) Synergies, (6) One-time transaction costs. Each affects pro forma earnings and therefore accretion/dilution."

The One Mistake Everyone Makes

Don't confuse "accretive" with "good deal."

A deal can be accretive and still be a terrible acquisition. Accretion just means EPS goes up in the short term. It doesn't mean:

• You paid a fair price
• The strategic rationale is sound
• Long-term value is created

Similarly, dilutive deals can be excellent if the strategic benefits outweigh the near-term EPS impact.

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