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How to Spread Capital Gains Over Several Years (With the Math)

By Hans Goldstein · Updated 2026-09-27

You spread capital gains over several years by getting paid over several years. Under the installment method in IRC §453, a seller reports gain only as principal payments come in, so a buyer's note paid over 5 or 10 years turns one huge tax year into several smaller ones. Smaller years keep more gain in the 0% and 15% brackets and can keep you under the 3.8% net investment income tax threshold, which is where most of the savings come from.

This page shows the mechanics and the math. For the full rules of the installment method, see the installment sale guide.

Why one big year costs more

Federal long-term capital gains are taxed at 0%, 15% or 20%, but the rate depends on where the gain lands on top of your other taxable income. The brackets are not per sale; they are per year. For 2026 (Rev. Proc. 2025-32 §3.03):

Filing status 0% up to (taxable income) 15% up to 20% above
Married filing jointly $98,900 $613,700 $613,700

On top of that, the 3.8% net investment income tax (NIIT, §1411) applies to the lesser of your net investment income or the amount your modified AGI exceeds $250,000 (joint) or $200,000 (single). Those thresholds are set in the statute and are not indexed.

Put a $1,000,000 gain into a single year and most of it sits in the 20% bracket and all of the excess over $250,000 of MAGI picks up 3.8%. Split it into ten $100,000 slices and each slice sits in the 0% and 15% brackets with no NIIT at all. Same total gain, very different total tax.

How to spread capital gains over several years

The tool is the installment sale: you sell, the buyer pays part at closing and signs a note for the rest, and you report gain as principal arrives. Each payment is split three ways:

  1. Return of basis (not taxed).
  2. Gain, found by multiplying the principal received by your gross profit percentage. See gross profit percentage for the formula.
  3. Interest, taxed as ordinary income every year.

The installment method applies automatically when at least one payment is received after the year of sale. You can elect out and report everything now; installment sale vs lump sum covers when that makes sense.

Common ways to get the payments spread:

Simple example: lump sum vs 5 years vs 10 years

Simple example. A married couple files jointly and has $60,000 of other taxable income every year (after deductions) and $90,000 of modified AGI before the sale. They sell land with a $1,000,000 long-term gain and no depreciation. We hold 2026 brackets and thresholds constant for every year, ignore state tax, and ignore the interest on the note (interest is taxed separately as ordinary income). Federal tax was computed with the IRC §1(h)(1) ordering in the Schedule D Tax Worksheet.

Lump sum 5 years 10 years
Gain per year $1,000,000 $200,000 $100,000
Gain taxed at 0% per year $38,900 $38,900 $38,900
Gain taxed at 15% per year $514,800 $161,100 $61,100
Gain taxed at 20% per year $446,300 $0 $0
Extra federal income tax per year $166,480 $24,165 $9,165
NIIT per year $31,920 $1,520 $0
Total tax on the gain, all years $198,400 $128,425 $91,650

Spreading over five years cuts the total by about $70,000. Spreading over ten cuts it by about $107,000, more than half. And the tax that is still owed is paid later, which is worth something on its own.

Notice the 0% line: every year, $38,900 of gain is tax-free because the couple's $60,000 of other income leaves $38,900 of room under the $98,900 line. In a lump-sum sale they get that room once. Over ten years they get it ten times.

Simple example: filling the 0% bracket

Simple example. A retired couple (joint) has $40,000 of other taxable income and $70,000 of MAGI. They sell a lot with a $300,000 long-term gain, same assumptions as above.

Lump sum 5 years ($60,000 a year)
Gain at 0% per year $58,900 $58,900
Gain at 15% per year $241,100 $1,100
Federal tax on the gain, all years $36,165 $825
NIIT $4,560 $0

Almost the whole gain is tax-free federally when it is spread, because each year's slice fits inside the 0% bracket. This is the "0% capital gains tax bracket" strategy people search for, and an installment note is the most common way to use it on a single large asset.

What spreading does not fix

Other side effects of spreading

A smaller gain each year can also help with things outside the income tax:

Spreading vs deferring vs avoiding

People use these words loosely. They are different:

Approach What happens to the gain
Installment sale Taxed as received, spread over the payment years
1031 exchange Postponed into replacement real estate
Hold until death Heirs may get a stepped-up basis (§1014)
Charitable trust Gain can shift into a tax-exempt trust, with a charitable gift attached

For a side-by-side of your own numbers, run the installment sale calculator. For how this fits with passive losses and a real estate exit plan, see the free book at The Waterfall Strategy.

Bottom line

You cannot spread a gain you were paid in full for, but you can spread a gain you are paid for over time. The installment method lets each year's slice use the 0% and 15% brackets and stay under the NIIT threshold, and on a large gain the difference between one year and ten can be more than half the tax. The trade-offs are credit risk, recapture that is taxed up front, and a longer wait for your money.

Questions to ask your CPA

Run your own numbers. Compare a cash sale, seller financing and a structured installment sale side by side, free.

Open the calculator Get the free book

Educational only, not tax, legal or investment advice. Examples are illustrative. Have your CPA or tax attorney review your facts before you act. Hans Goldstein is a licensed insurance agent (CA Insurance License #4273294) and is not a CPA or attorney. He is paid a commission only if a structured installment sale is funded; seller financing pays him nothing. Disclosures.