Warren Buffett has spent 60 years turning modest stakes in companies like Coca-Cola (NYSE:KO | KO Price Prediction) and American Express (NYSE:AXP) into some of the largest unrealized gains in American investing history. If he ever sold, the tax bill would be staggering — which is exactly why a proposal now circulating in Washington has investors buzzing.
The Trump administration is weighing a change that would let long-term investors subtract inflation from their gains before the IRS ever gets a cut. National Economic Council Director Kevin Hassett has confirmed the White House is developing capital gains proposals ahead of November’s midterms, and inflation-indexed cost basis sits at the center of it.
Naturally, Buffett’s name keeps coming up as the ultimate test case. Could America’s most famous buy-and-hold investor end up owing nothing at all? Not quite — but the real answer is still worth understanding.
What Indexing Actually Changes
Capital gains taxes have always had a blind spot: they can’t tell the difference between a dollar of real profit and a dollar of pure inflation. Buy a stock for $50 and sell it years later for $150, and the IRS treats the entire $100 as taxable income — even if half of that increase simply reflects a weaker dollar rather than a stronger company.
Indexing fixes that distortion by adjusting an investor’s original purchase price upward to reflect inflation accumulated over the holding period, so the tax bill reflects actual wealth creation rather than a currency illusion. Republican Sens. Ted Cruz and Tim Scott pushed a version of this idea earlier in 2026, and other lawmakers have separately urged Treasury Secretary Scott Bessent to implement it through executive action. Neither path has become law. The Bipartisan Policy Center has already begun weighing in on whether Treasury even has the legal authority to act alone.
Buffett’s Bill Shrinks — It Doesn’t Vanish
This is where the “$0 tax bill” headline falls apart. Berkshire Hathaway‘s (NYSE:BRK-A)(NYSE:BRK-B) core Coca-Cola position, built between 1988 and 1994, carries a split-adjusted cost basis near $3.25 a share. Cumulative inflation since then — roughly 2.7x — would push that adjusted basis to somewhere around $8 to $9. With Coca-Cola trading in the high $80s, that adjustment shaves a few dollars off the taxable gain per share. It doesn’t touch the other $80-plus.
| Holding | Original Split-Adjusted Basis | Inflation-Adjusted Basis | Recent Price |
| Coca-Cola (1988–94 buys) | ~$3.25 | ~$8–9 | $86 |
| American Express (1990s buys) | ~$8–9 | Modest uplift | $339 |
| Berkshire Hathaway (1960s buys) | Single digits | 10x+ adjustment | $770,311 |
Even applying a tenfold inflation adjustment to Berkshire’s 1960s-era shares leaves an enormous real gain fully taxable. In short, indexing rewards patience and punishes phantom inflation gains — it doesn’t erase decades of genuine outperformance.
The bigger relative winners are investors whose holdings roughly tracked inflation, where a shrinking taxable base can turn a modest gain into a negligible one.
The Price Tag Nobody’s Ignoring
Granted, this isn’t a free lunch for the Treasury. The Cruz-Scott version of indexing was estimated to reduce federal revenue by about $200 billion. The Committee for a Responsible Federal Budget, citing Yale Budget Lab figures, warned the executive-action route alone could add $170 billion to $950 billion to the national debt by 2035 — against a Congressional Budget Office deficit estimate near $1.8 trillion for the first 10 months of fiscal 2026 alone.
CRFB president Maya MacGuineas called it a deficit-financed tax cut enacted “by executive fiat.” That’s a real headwind against fast implementation, especially given the legal authority questions.
Key Takeaway
Nothing here is enacted law, and investors shouldn’t reposition portfolios on a headline. But the direction is clear: indexing capital gains would meaningfully lower tax bills on long-held winners, especially for shareholders who’ve held through inflationary stretches without generating outsized real returns.
For Buffett-style buy-and-hold investors, the savings are real but proportionally small next to decades of genuine wealth creation. Smart investors should watch for actual legislative or Treasury action — not just letters and trial balloons — before assuming this changes their after-tax math and liability.
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