Combining 1031 and Section 121 on a converted rental

By Tom, CPA · Updated October 27, 2026

Part of: Rental Property Taxes

TL;DR: If you lived in a home 2 of the last 5 years and then rented it out, Rev. Proc. 2005-14 lets you apply the section 121 exclusion first (up to $250,000 single or $500,000 joint) and defer remaining gain, including depreciation, with a 1031 exchange. Going the other direction, a home acquired by 1031 needs a 5-year hold before 121 applies.

Educational only, not tax, legal, or investment advice. Examples are illustrations, not predictions. Rules and limits change; verify current figures and talk to a qualified professional about your situation.

Two of the most generous provisions in the tax code are the home sale exclusion and the like-kind exchange. Using both on one property is the tax equivalent of a double coupon day. Rev. Proc. 2005-14 confirms it's allowed, with rules about which coupon goes first. This guide covers the direction most FIRE folks care about: you lived in the home, then rented it, and now you want to sell.

Background reading: the home sale exclusion and 1031 basics.

CPA Warning Label: The 2-of-5-year window closes 3 years after you move out. Miss it and the $250,000 or $500,000 exclusion disappears from the plan.

Rev. Proc. 2005-14 combo

Rev. Proc. 2005-14 addresses property that qualifies under both sections, typically a former principal residence converted to rental or a home with a business-use portion. Its main rules:

1. Apply 121 first. The exclusion applies to gain on the exchange before section 1031.
2. Then 1031 defers the rest, including gain attributable to depreciation after May 6, 1997, which section 121 can't exclude.
3. Boot is offset by the exclusion. Cash or other boot received is taxable only to the extent it exceeds the gain excluded under 121.
4. Basis of the replacement is increased by the gain excluded under 121, so excluded gain isn't taxed later.

The eligibility for 121 is the familiar test: you owned and used the property as your principal residence for at least 2 of the 5 years before the sale. So a converted rental qualifies for both only if the exchange happens within 3 years of moving out. The property also must be held for investment at the time of the exchange to qualify for 1031, which a rental is.

Nonqualified use

Since 2009, section 121(b)(5) reduces the exclusion for periods of "nonqualified use" (time the property wasn't your principal residence). But there's a crucial exception: any period after the last date you used it as your principal residence, within the 5-year window, is not nonqualified use. So for the home-then-rental sequence, renting it after you move out doesn't shrink the exclusion. Nonqualified use mainly bites when a rental or second home later becomes your residence. See moving into your rental for that direction.

5-year hold after exchange

Section 121(d)(10) covers the reverse direction: if you acquired the property in a 1031 exchange, you can't use the 121 exclusion on its sale during the 5 years beginning on the date you acquired it. The idea was to stop people from exchanging into a rental, moving in after a few months and excluding gain that was mostly deferred rental gain.

Even after 5 years, nonqualified use rules prorate the exclusion based on the time it was a rental after 2008. And depreciation taken is taxed when you sell.

Example

Illustration (made-up numbers): Frugal Fran and her spouse bought a home in 2016 for $400,000 and lived in it until June 2024. They rented it from July 2024 and exchange it in October 2026 for $1,100,000 (after selling costs). Depreciation claimed during the rental years: about $30,000. Adjusted basis: $370,000. Realized gain: $730,000.

They exchange into a $900,000 rental and receive $200,000 of cash. Under Rev. Proc. 2005-14, the cash boot is offset by the $500,000 excluded gain, so it's not taxed. The remaining $230,000 of gain is still deferred. Their replacement basis: $900,000 minus the $230,000 deferred gain = $670,000. Compare that to a regular sale: $230,000 taxable, including $30,000 at up to 25%.

Had they waited until 2028 to sell, they would fail the 2-of-5-year test (moved out mid-2024). The exclusion would vanish, and the whole $730,000 would need deferral.

Timeline view: June 2024 move-out; 2-of-5 test satisfied through about June 2027; the rental needs to have been genuinely rented at fair rent before the exchange; QI engaged before the October 2026 closing; replacement identified within 45 days and closed within 180 days. If they later move into the replacement property, the 5-year clock under 121(d)(10) starts on the replacement closing date, not the original purchase.

The mixed-use variant: duplexes and home offices

Rev. Proc. 2005-14 also covers a single property used partly as your home and partly for rental or business at the same time, like an owner-occupied duplex. If the rental unit is a separate dwelling unit, section 121 doesn't apply to the gain allocable to it (Treas. Reg. 1.121-1(e)). That rental portion can be exchanged under 1031, while the home portion uses the exclusion.

Illustration: Fran owns a duplex, living in one side and renting the other. Sale price $800,000; gain $300,000, split 50/50 by square footage. The $150,000 home-side gain is excluded. The $150,000 rental-side gain (including depreciation on that side) can be deferred if she exchanges the rental portion's proceeds, about $400,000 of value, into investment property. She could buy a $400,000 rental and keep the home-side proceeds as tax-free cash. More on owner-occupied multi-units in house hacking taxes.

Reporting it

Report the sale on Form 8824 (for the exchange portion) and follow the Form 8824 instructions for the section 121 exclusion: the excluded gain is reported on the form so the math nets correctly. Form 4797 carries depreciation recapture details if any gain is recognized. Keep proof of residence for the 2 years: driver's license, voter registration, tax returns, utility bills. The IRS may ask years later, when you sell the replacement.

Pitfalls

• The 3-year window. Moving out starts a clock. Put the deadline on the calendar.
• Investment intent. You need to actually rent the property at fair rent before exchanging. A house that sits empty, or one you moved out of a week before closing, has weaker investment intent. Facts and circumstances apply.
• Depreciation is never excluded. Claim it anyway; the IRS reduces basis by depreciation "allowed or allowable," so skipping it only hurts you.
• Married couples: the $500,000 needs both spouses to meet the use test and one to meet ownership, and neither excluded another home sale in the prior two years.
• Replacement property: if you later move into it, the 5-year rule and nonqualified use apply.
• State tax: most states follow 121 and 1031, but check, especially if moving between states.

Choosing between exclusion only, exchange only, or both

Sometimes the combo isn't best. If gain is under your exclusion amount, just sell; a 1031 adds cost and complexity for nothing except deferring depreciation recapture. If you want to be done with landlording, sell and take the exclusion, paying tax on the rest. If you want to keep investing in real estate and the gain exceeds the exclusion, the combo is powerful. Think about what happens after: an exchange keeps you a landlord, with a new set of tenants and a new depreciation schedule, and with the deferred gain carried into the next property until you sell without exchanging or die holding it. If you're a few years from wanting out, a sale with the exclusion can be cleaner. Model each path with the 1031 vs sell calculator and read converting your home to a rental for the basis rules on the way in.