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Installment Sale Gain and Opportunity Zones: Timing the 180 Days

By Hans Goldstein · Updated 2026-09-27

Installment sale gain can be deferred into a qualified opportunity fund (QOF) one payment at a time. Under Reg. §1.1400Z2(a)-1(b)(11)(viii), gain you recognize under the installment method is eligible gain, and you may start each 180-day investment window either on the date you receive a payment or on the last day of that tax year. Only the gain portion needs to be invested, not the full payment. For money invested after December 31, 2026, the rebuilt Opportunity Zone rules give a rolling five-year deferral, a 10% basis step-up at five years, and tax-free growth after ten years.

This page walks through the timing, runs a labeled simple example, and explains the 2026 handoff. For how installment gain is measured in the first place, see the installment sale guide.

The rule in the regulation

The key text, from Reg. §1.1400Z2(a)-1(b)(11)(viii)(B):

"For gains reported on the installment method, an eligible taxpayer may treat the date the payment on the installment sale is received or the last day of the taxable year in which the eligible taxpayer would have recognized the gain under the installment method as the beginning of the 180-day period ... if an eligible taxpayer receives one or more payments on an installment sale and treats the date the payment on the installment sale is received as the beginning of the 180-day period, each payment will begin a new 180-day period."

The statute defers "so much of such gain as does not exceed the aggregate amount invested by the taxpayer in a qualified opportunity fund during the 180-day period" (§1400Z-2(a)(1)(A)). So you invest dollars equal to the gain, and your principal recovery stays yours.

Choice 180-day window starts Best when
Payment-date method Each payment's receipt date You want to invest as cash arrives
Year-end method December 31 of the year the gain is recognized You want to pool a year of payments and invest once

The regulation also confirms this applies to installment sales that occurred before December 22, 2017, so an old note still throwing off gain can qualify, subject to the 2026 handoff below.

Which part of each payment is eligible

Each principal payment splits into basis recovery and gain at your gross profit percentage. Interest is ordinary income and is not eligible. Recapture is also out:

Piece of the payment Eligible for QOF deferral?
Interest No
Basis recovery Not gain, nothing to defer
§1245 recapture No, and it is taxed in the year of sale anyway under §453(i)
Ordinary §1250 recapture No
Unrecaptured §1250 gain (25% maximum) Yes; it keeps its 25% character when later included
§1231 gain above recapture Yes
Other long-term capital gain Yes

On recapture timing, see installment sale depreciation recapture. When deferred gain is later included, Reg. §1.1400Z2(a)-1(c)(1)(i) says it keeps the attributes it would have had, so a 25% gain comes back as 25% gain.

Old rules vs new rules: the 2026 handoff

Invested on or before Dec. 31, 2026 Invested after Dec. 31, 2026
Deferral ends December 31, 2026 (or earlier sale) Earlier of sale or 5 years after the investment
Basis step-up Old 10% and 15% steps mostly unreachable now 10% at 5 years; 30% for a qualified rural fund
10-year exclusion Yes, under old rules Yes; fair market value basis on sale, capped at year-30 value
Zone map Current designations New designations from the July 1, 2026 determination date
Source §1400Z-2(b)(1)(B); Reg. §1.1400Z2(a)-1(b)(40) §1400Z-2 as amended by P.L. 119-21 §70421

Two practical consequences for a seller on a note:

  1. Installment gain invested in late 2026 buys almost nothing. Under the old rules, remaining deferred gain is taxed on December 31, 2026. The regulation puts it plainly: after that date "an eligible taxpayer's remaining deferred gain is $0."
  2. Payments in 2027 and later line up with the new program. Amounts invested after 2026 get the rolling five-year clock. Each investment has its own clock, so a note paying every year creates a ladder of five-year inclusion dates.

Transition questions, such as how an installment sale closed before 2027 interacts with investments made after 2026, are addressed in IRS transitional guidance (Notice 2026-40). Confirm your specific timing with your CPA before relying on it.

Simple example: a note feeding a fund

Simple example. Assumptions: you sell land for $1,500,000 with a $300,000 basis on a note. Gross profit percentage: ($1,500,000 minus $300,000) divided by $1,500,000 = 80%. The buyer pays $200,000 of principal each year in 2027 through 2033 plus interest after a $100,000 down payment in December 2026. No depreciation. You use the payment-date method.

Payment Principal Gain (80%) Invest by Deferred gain taxed Taxed amount after 10% step-up if held 5 years
Dec. 2026 down payment $100,000 $80,000 Old rules: taxed Dec. 31, 2026 2026 No step-up; little point investing
Mar. 1, 2027 $200,000 $160,000 Within 180 days 2032 (5 years after investment) $144,000
Mar. 1, 2028 $200,000 $160,000 Within 180 days 2033 $144,000
Later years $200,000 each $160,000 each Each within 180 days 5 years after each $144,000 each

You invest $160,000 from each $200,000 payment and keep the $40,000 basis recovery. The fund pays you nothing on schedule, so the tax on the $144,000 in year five comes out of your pocket. If you hold a fund interest ten years, growth on it is excluded when you sell (subject to the 30-year cap).

Model the note's cash flow and tax by year in the calculator.

Opportunity zone fund vs just holding the note

Keep the installment note Invest note gain in a QOF
Cash to you Interest plus principal on schedule Only the basis portion of each payment
Gain taxed As each payment arrives 5 years later, 10% smaller
Growth None; fixed interest Fund's growth, tax-free after 10 years
Risk Buyer default, secured by the property Fund and real estate risk; illiquid
Suspended passive losses Meet the gain as it arrives Have nothing to offset while gain is deferred

The note is income; the fund is a growth bet. They can be combined, but the fund is a security with its own risks and fees. Hans does not sell QOF interests.

If you are still deciding whether to spread the gain at all, see installment sale vs lump sum. Reporting still runs through Form 6252 for the installment gain, with the deferral election made on Form 8949 and the fund investment tracked on Form 8997.

Bottom line

Installment gain can go into an opportunity fund payment by payment, and each payment can start its own 180-day clock. Invest only the gain, not the recapture or interest. Money invested before 2027 buys almost no deferral; payments received and invested after 2026 fit the new five-year rolling program. Treat it as an investment decision first and a tax decision second.

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.