Accretion/dilution analysis

When one public company buys another, the first number every headline quotes is whether the deal is accretive, meaning pro-forma EPS comes out above the acquirer's standalone EPS, or dilutive, meaning it comes out below. You need to be able to compute it in three flavors in under ten minutes. Then you need to be the person in the room who knows it proves almost nothing.

Memorize this pair of companies as the base case. Acquirer A has net income of $1,000m, 500m shares, EPS of $2.00 and a price of $40, so its P/E is 20×. Target T has net income of $300m, 200m shares, EPS of $1.50 and a price of $18, so its P/E is 12×. A offers a 25% premium, or $22.50/share. That makes equity consideration $4,500m, and the P/E paid = 4,500/300 = 15×.

How do you calculate accretion and dilution?

One universal machine works for any consideration mix:

Pro-forma EPS = (NI_A + NI_T + after-tax synergies
                 − after-tax interest on new debt
                 − after-tax interest FOREGONE on cash spent
                 − after-tax amortization of new deal intangibles)
                ÷ (Shares_A + new shares issued)

Take all-stock first. New shares = consideration ÷ acquirer's price = 4,500/40 = 112.5m. Pro-forma EPS = (1,000+300)/(500+112.5) = 1,300/612.5 = $2.12, so +6.1% accretive. As a quick rule, an all-stock deal is accretive iff the acquirer's P/E > P/E paid. Here 20× > 15×, so it checks out. You're swapping paper earning a 5.0% earnings yield (1/20) for earnings bought at a 6.7% yield (1/15). It's pure multiple arithmetic. Notice that the target's standalone 12× doesn't matter once the premium moves the paid multiple to 15×.

Now the all-cash, debt-funded version, at 6% pre-tax and 25% tax, which makes the after-tax cost 4.5%. Incremental after-tax interest = 4,500 × 4.5% = 202.5. Pro-forma EPS = (1,300 − 202.5)/500 = 1,097.5/500 = $2.20, so +9.7% accretive. For cash, the quick rule is that a deal is accretive iff the target's earnings yield on the price paid > the after-tax cost of funds. Here 300/4,500 = 6.67% > 4.5%, so it passes.

What about mixed deals and cash on hand?

A mixed 50/50 deal splits the difference. Cash of 2,250 costs 101.25 of after-tax interest, and stock of 2,250 means 56.25m new shares. Pro-forma EPS = (1,300 − 101.25)/556.25 = $2.16, or +7.8%, between the two purebreds, as you'd expect.

Cash on hand shows the accretion illusion at its purest. Fund the deal from the balance-sheet cash pile earning 4% pre-tax. Foregone after-tax interest = 4,500 × 3% = 135, so EPS = (1,300 − 135)/500 = $2.33, or +16.5%. The worst earnings on the planet clear a 3% hurdle. In a low-rate world, essentially every cash deal is "accretive", which tells you the metric's bar is lying on the floor. When a CEO leads with "immediately accretive," ask first: against what cost of capital? The hurdle buried in the EPS math is the cost of funds, 3 to 4.5% here, while the cost of capital is ~9%.

How can purchase accounting flip the answer?

One refinement, amortization, shows how accounting can flip the headline. Purchase accounting writes up the target's identifiable intangibles. Suppose $1,500m goes into customer relationships amortized over 10 years. That's $150m/yr pre-tax, or $112.5m after tax. Now the all-stock deal becomes (1,300 − 112.5)/612.5 = $1.94, which is −3.1% dilutive. Same deal, same cash flows, opposite headline. Companies invented "adjusted/cash EPS excluding deal amortization" for this reason. It's also how Microsoft could pitch Activision as accretive to non-GAAP EPS from close. That was a real deal, $68.7bn all cash, $95.00/share, closed October 2023, the largest gaming acquisition ever. Non-GAAP EPS excludes the very amortization the purchase creates, and neither headline changes a single cash flow. So you're seeing both tricks at once. The metric is soft, and its definition is negotiable.

Does accretion mean the deal creates value?

Accretion isn't value creation, and conservation of value proves it with numbers. Run it on the all-stock base case. Standalone values are A = $20,000m and T = $3,600m. Suppose real synergies are worth $600m PV. Combined value = 20,000 + 3,600 + 600 = $24,200m. After the deal, A's old holders own 500/612.5 = 81.63%. That's worth 0.8163 × 24,200 = $19,755m, so they're $245m poorer in a deal that raised their EPS 6.1%. T's holders own 18.37%, or $4,445m, which leaves them $845m richer. That's their $900m premium, netted against their share of the dilution.

Synergies created $600m, the only value creation anywhere in the arithmetic. Yet the deal transferred more than that to the target. EPS rose because A bought earnings at a lower multiple than its own. Value fell because it paid a premium ($900m) larger than the synergies ($600m). That inequality, premium vs PV of synergies, is the entire economics of M&A, and EPS accretion is orthogonal to it.

It cuts the other way too. A high-multiple deal for a fast grower can be dilutive and brilliant. Say A buys growth company G, with NI of $100m, at a paid P/E of 30×, all stock. EPS = 1,100/575 = $1.91, which is −4.3% dilutive. It's a bad deal only if the price exceeds G's value. Either way, the dilution headline is noise.

So say it once, cleanly. Accretion measures the blending of multiples, and value creation measures price against worth. They're different questions that occasionally share an answer.

How does accretion and dilution work in India?

On the India panel the mechanics are identical on the NSE, with two local flavors.

1. All-stock deals happen through NCLT schemes of arrangement expressed as swap ratios. HUL absorbed GSK Consumer Healthcare (Horlicks) in an all-stock merger completed in April 2020 at 4.39 HUL shares per GSK CH share (~₹31,700 cr). Those are real terms, so verify them in the scheme documents on BSE/NSE. It's a premium-multiple acquirer using its expensive paper, textbook multiple arithmetic. HDFC Ltd merged into HDFC Bank in 2023 at 42 : 25. The registered-valuer reports and fairness opinions attached to scheme filings are free masterclasses. They contain full comps tables and DCFs you can audit.
2. Promoter-controlled acquirers avoid stock deals that dilute the family's stake below control comfort, so India skews to cash consideration. When a promoter does issue stock, ask what that says about how they value their own paper. It's the buyback logic, turned inside out.