Tax Torpedo Drill Down: How a 0% Capital Gain Can Cost You 30%

Tax Torpedoes
Written By Larry Hall

Written by Larry Hall
July 31, 2026

This article is a continuation of my 8/11/2025 blog post, “Tax Torpedoes: How the Tax Man Can Getcha.” Today we examine the issue of long-term capital gains rate disruption. Long-term capital gains are profits you earn from selling an asset held for more than one year, and are taxed at marginal rates of 0%, 15%, or 20%. What many people don’t understand is that capital gains are stacked on top of your other income. A decision unrelated to realizing a capital gain such as an IRA distribution to cover an unexpected bill, a Roth IRA conversion, a short-term CD maturing with interest, or a stock or real estate sale can all push what you thought was a 0% or 15% gain into the 15%, or even the 20% category.

🧾 A $20,000 Decision That Cost $6,048

Imagine a hypothetical couple. Ray and Diane are both 68 and live in New Hampshire. In 2026 they sell a parcel of land bought back in 1994 and realize a $140,000 capital gain.

Their other income for the year is: $40,000 of Social Security benefits (of which $34,000 is taxable), $26,000 in annuity income, $16,000 of Individual Retirement Account (IRA) withdrawals, and $8,000 of interest. That’s $84,000, not including the gain.

Then the roof starts leaking. They need $20,000. They can take it out of the IRA, or they can take it out of savings. Money is money. Right? What difference does it make which account they take it from?

If Ray and Diane take the $20,000 from an IRA account, their total federal income tax is $23,970,

If they would have taken the money from savings instead, the tax would have been $17,922.

In other words, taking the money from the IRA cost an additional $6,048 in tax. That’s a 30% marginal tax rate that could have been avoided. Of course Ray and Diane may eventually have to pay tax on their IRA withdrawals, but not at a 30% rate.

In case you’re wondering, the extra withdrawal did not drag more of their Social Security income into taxable status. 85% of their Social Security benefits are taxable either way. I’ll address Social Security taxation in another article.

📈 Why Gains "Stack"

Here's what causes the damage.

Your ordinary income, including wages, pensions, IRA and 401(k) withdrawals, taxable Social Security, interest, Roth conversions, all fill the bottom of the bucket first. Long-term capital gains and qualified dividends sit on top, and they're measured against their own set of thresholds based on your total taxable income.

For 2026, married filing jointly:

  • 0% on long-term gains until taxable income reaches $98,900

  • 15% from there up to $613,700

  • 20% above that

For single filers the 0% ceiling is $49,450 and the 15% band runs to $545,500. For head of household it's $66,200 and $579,600.

The word that matters is taxable income. That means combined ordinary income and gains, after deductions. Every dollar of ordinary income you add lifts the whole stack. A dollar of IRA withdrawal is taxed at your ordinary rate and may displace a dollar of gain from 0% into 15%, or from 15% into 20%.

🪜 Three Things One Extra Dollar Did

Let’s look at Ray and Diane's roof money decision a bit more closely.

That $20,000 IRA withdrawal had three effects, and only one of them was obvious.

It got taxed at 12%, their ordinary bracket, which added $2,400 to their tax. That was expected.

It shrank a deduction. This one is new and easy to miss. The $6,000-per-person senior deduction created by the One, Big, Beautiful Bill (available 2025 through 2028 for anyone 65 or older) begins to phase out once Modified Adjusted Gross Income (MAGI) passes $150,000 ($75,000 for singles). Ray and Diane were already past that because of the land sale, so the extra $20,000 cost them another $2,400 of deduction. Tax on that: $288.

It pushed gains uphill. Between the withdrawal itself and the lost deduction, their taxable ordinary income rose by $22,400, which shoved $22,400 of land-sale gain out of the 0% bracket and into the 15% bracket. Tax on that: $3,360.

$2,400 plus $288 plus $3,360 is $6,048. Three effects, one decision, and only the first one shows up on a bracket chart.

💣 And Then There's the 3.8%

For larger gains, a fourth layer may appear.

The Net Investment Income Tax (NIIT) adds 3.8% on top of whatever you already owe. It applies to the lesser of your net investment income or the amount your MAGI exceeds $250,000 (married filing jointly), $200,000 (single or head of household), or $125,000 (married filing separately).

Those thresholds are worth staring at for a second, because they have not moved since 2013. They aren't indexed for inflation. Congress set them once and walked away. Every year, ordinary inflation walks a few more households into a tax that was pitched as a levy on the wealthy.

Suppose Ray and Diane sell the family camp instead, with a $300,000 gain. Their MAGI lands at $384,000. The senior deduction is gone entirely. About $50,400 of the gain still gets the 0% rate, the stacking rule cuts both ways and it helps here, but $249,600 is taxed at 15%, and $134,000 of it also picks up the 3.8% NIIT. Total federal tax: roughly $47,856.

The effective rate on that last slice of gain isn't 15%. It's 18.8%.

🏔️ A New Hampshire Wrinkle

Good news first: New Hampshire has no general income tax, and the old Interest & Dividends Tax was repealed effective January 1, 2025. For a Granite Stater selling New Hampshire property or New Hampshire-held securities, the federal number is the whole number. That's unusual, and it means federal timing decisions carry the entire weight. There's no state layer to consider.

If you live in another state, you may have to consider state taxes as well. Depending on the state you live in, there may be a significant additional tax.

🧭 What to Do About It

Think about tax consequences before you sign. A projection in September 2026 can save a lot of heartburn in April 2027. The question isn't "what marginal rate do I pay?" You have to consider all potential tax triggers.

Ask where cash should come from. Savings, a taxable brokerage account, and an IRA all spend identically at the lumberyard but may cost wildly different amounts on the return. Ray and Diane's $6,048 tax on the IRA withdrawal could have been substantially reduced.

Consider spreading the gain. An installment sale on real estate can move part of the gain into a later year, keeping more of it in the 0% or 15% band and possibly under the NIIT threshold. Not always the right answer, but worth considering.

Harvest losses deliberately. Realized losses offset realized gains dollar for dollar. If you have a position underwater, the year of a big sale is when it's most valuable.

Watch Roth conversions in a sale year. Conversions can make sense. Doing one the same year you sell appreciated property may leave you with an unnecessarily large tax bill.

Look at the whole return, not the gain. Deductions that phase out, IRMAA two years down the road, taxable Social Security, and NIIT must all be considered when realizing a capital gain. That's the theme of this whole series: the tax code punishes decisions made one line at a time. You have to consider all the consequences.

Selling something big this year?

If you need help considering the tax consequences of a large transaction, I am happy to help. A consultation may save you from a nasty surprise when tax time rolls around. Contact me for help.

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This article is for informational purposes only and does not constitute professional tax advice. For guidance on your specific situation, consult a qualified tax professional.

📚 Sources & Further Reading

Larry Hall

Lawrence (Larry) Hall, CPA, EA is a Grantham, New Hampshire based tax professional. He holds MS in Accounting and MBA degrees from Plymouth State University, where he taught accounting for several years. He thinks a lot about tax matters so you don’t have to.

https://HallTaxPro.com
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