Section 121 of the Internal Revenue Code is the provision that lets most homeowners sell a primary residence without owing federal capital gains tax on some or all of the profit. It is narrower than people assume, tied to specific ownership and use tests rather than simply owning a home, and in a market with New York City's price appreciation, it frequently covers only part of a large gain rather than the whole thing. Knowing exactly what the rule requires, and where it stops, matters more here than in most parts of the country.
The Ownership and Use Tests
To qualify, the seller must have owned the property and used it as their main home for at least 24 months out of the 60 months immediately before the sale. Both tests have to be satisfied, and while the 24 months do not need to be consecutive, they do need to fall within that five-year window. An owner who bought a Manhattan condo, rented it out for three years, then moved in for the final two years before selling would generally satisfy both tests, since the use period falls within the required window even though it came later in the ownership timeline.
Exclusion Amounts and the Married-Filing-Jointly Rule
A single filer can exclude up to $250,000 of gain, and a married couple filing a joint return can exclude up to $500,000, but the higher amount requires that both spouses meet the ownership and use tests individually, not just that the couple files jointly. A recently married couple where only one spouse owned and lived in the property for the required period is limited to the $250,000 exclusion for that sale, not the full $500,000, until the other spouse independently satisfies the test.
The Once-Every-Two-Years Limit
The exclusion generally cannot be claimed more than once in any two-year period, which matters for an owner who sells one property and moves quickly into another with plans to sell again soon. A seller who used the exclusion on a Brooklyn co-op last year and is now closing on a second sale within the same two-year window may find the exclusion unavailable for the second sale, regardless of how clearly the ownership and use tests are otherwise met.
Partial Exclusions for an Unqualifying Sale
A seller who does not meet the full two-year test because of a job change, health issue, or another qualifying unforeseen circumstance may still be eligible for a reduced exclusion, calculated proportionally based on how much of the two-year period was actually met. This partial exclusion is not automatic and depends on the specific circumstances meeting the IRS's definition of a qualifying reason, which is stricter than a simple personal preference to move.
How a Rental Period Affects the Exclusion
A homeowner who rented out a New York City property for a stretch of years before moving back in and selling still needs the total qualifying use to reach 24 months within the five-year window, and any depreciation claimed during the rental period is generally not eligible for exclusion even if the rest of the gain is. A seller in this position should separate the depreciation-related portion of the gain from the appreciation portion before assuming the full exclusion applies, since the two are calculated on different rules even within a single sale of the same property.
Common 1031 Exchange Questions
Do the 24 months of ownership and use need to be the same 24 months?
The ownership test and the use test are measured separately but must both total at least 24 months within the same five-year window before the sale. In most cases the periods overlap substantially, but they are evaluated as distinct requirements.
Can a couple claim the full $500,000 exclusion if only one spouse is on the deed?
The ownership test generally requires the property to have been owned by at least one spouse, but the use test requires both spouses to have lived in it for the required period for the full $500,000 exclusion to apply on a joint return.
How often can the Section 121 exclusion be used?
Generally no more than once every two years. A seller who used the exclusion recently on another property sale may not be able to claim it again until that two-year window has passed, even on a fully qualifying second sale.
What counts as a qualifying unforeseen circumstance for a partial exclusion?
The IRS recognizes specific categories including certain job-location changes, health-related moves, and other defined hardship circumstances. A personal decision to move for convenience or a better price generally does not qualify for the reduced exclusion.
Does the Section 121 exclusion apply to a co-op or condo the same as a house?
Yes. Co-op shares and condo units qualify under the same ownership and use tests as a single-family house, since the exclusion is based on how the property was used rather than its legal form.
