Selling the House She Bought for $140,000 in 1988 Will Cost a 74-Year-Old $90,000, Thanks to a Tax Break Frozen Since 1997

A widow in her mid-70s bought a modest home in 1988 for $140,000. Today, she is ready to downsize, and a local agent tells her the property will fetch somewhere in the mid-$700,000s. She assumed the profit was hers to keep. Then her CPA sent an email with a number she was not expecting: a roughly $90,000 federal and state tax bill on the sale.

She is running headfirst into a rule Congress wrote in 1997 and has not touched since: the Section 121 home-sale exclusion.

Why a 29-Year-Old Tax Break Is Now the Problem

The Taxpayer Relief Act of 1997 let homeowners exclude up to $250,000 of gain on a primary residence if single, or $500,000 if married filing jointly. Those thresholds were never indexed to inflation. They are the same numbers today that they were the year the DVD player launched.

Meanwhile, housing has done what housing does. The S&P CoreLogic Case-Shiller U.S. National Home Price Index sits at near 337, up about half a percent from the prior month, and the index is based on January 2000 = 100. A home bought in 1988 has ridden nearly four decades of nominal appreciation. The median new home in the U.S. now sells for roughly $410,700, and coastal and desirable suburban markets are well above that.

The result: a homeowner who paid $140,000 and is now selling for the mid-$700,000s has a gain that blows through the single-filer exclusion by a couple hundred thousand dollars. That excess is taxed as a long-term capital gain, typically at 15%, plus the 3.8% net investment income tax if her modified AGI clears the threshold, plus state income tax. Stack those, and $90,000 to the government is realistic.

One Number That Actually Drives the Bill

Every other variable is a rounding error compared to her cost basis. Basis is what she paid, plus the cost of capital improvements over 38 years of ownership, plus selling costs like the agent commission and title fees. Every legitimate dollar added to basis is a dollar that does not get taxed at roughly 18% to 24% all-in.

Most long-tenured owners understate basis badly. A new roof in 2004, the kitchen remodel in 2011, the HVAC replacement in 2018, the deck, the driveway, the finished basement: these count as capital improvements that add to basis. If she can document $60,000 of improvements she forgot about, she just erased more than $10,000 of tax at the margin.

Two Realistic Paths, and One Clear Winner for Most People

She has two credible strategies. They are not equal.

1. Sell now and reconstruct basis aggressively. Pull permits from the town, credit card statements, canceled checks, and contractor invoices. Add every improvement, plus the 5% to 6% in selling costs. This is boring work that pays roughly $200 to $240 per hour in tax saved for every dollar of improvements documented. For a homeowner facing a $90,000 bill, spending a weekend in the filing cabinet is the highest-return activity available.
2. Do not sell. Let the heirs inherit. Under current law, appreciated assets receive a step-up in basis at death, wiping out the embedded capital gain entirely. If she does not need the equity to fund retirement, and her heirs will sell the house shortly after inheriting, the federal tax on the gain effectively disappears. A reverse mortgage or a HELOC can unlock some cash without triggering the sale.

For most 74-year-olds who genuinely want to downsize, path one wins. Staying in a house you no longer want purely to dodge tax is the classic case of the tail wagging the dog. Maintenance, property tax, insurance, and stair-climbing risk all compound. And with existing-home sales running at just 3.98 million annualized in August 2026, the lowest in the recent series and inside the guide’s soft-market range, waiting for a hotter market is a gamble.

What to Do This Month

Two things matter more than anything else. First, rebuild basis before you list. Every receipt is worth real money. Second, if you were widowed recently, check the calendar carefully: a surviving spouse can still claim the full $500,000 exclusion for up to two years after the spouse’s death, provided the ownership and use tests are met. Missing that window by a few months is the most expensive mistake in this scenario, and it is entirely avoidable.

The exclusion may get raised. Bills to lift it have been introduced repeatedly, and planning around a law change stuck for 29 years is wishful thinking. This frozen threshold is one of several IRS quirks that quietly cost retirees six figures (we mapped nine of them in a free guide to the traps hiding in the tax code).

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