Section 121 Partial Home Sale Exclusion Calculator 2026
Calculate the partial Β§121 home sale exclusion when sold before the 2-year test. Pro-rate $250K/$500K based on months of ownership/use. Job change, health, divorce qualifying reasons.
$
Sale price minus adjusted basis minus selling costs Months owned out of last 5 years (max 24 for full)
Months lived as primary home (must equal ownership or less)
$
Determines LTCG (>1 yr) vs STCG rate
$0
Partial Exclusion Amount
0%
Exclusion Fraction (months/24)
$0
Taxable Gain After Exclusion
$0
Capital Gains Tax Owed
Exclusion Calculation Detail
| Step | Calculation | Amount |
|---|
How the Β§121 Partial Exclusion Works
The full Β§121 exclusion ($250,000 single / $500,000 married jointly) requires 2 years of both ownership and use. When you sell before meeting this test but have a qualifying reason, the IRS allows a pro-rated partial exclusion.
The Formula
Qualifying Months = min(Ownership Months, Use Months, 24)
Exclusion Fraction = Qualifying Months / 24
Partial Exclusion = Full Exclusion Γ Exclusion Fraction
($250K single Γ fraction, or $500K MFJ Γ fraction)
Taxable Gain = max(0, Realized Gain β Partial Exclusion)
LTCG Tax = Taxable Gain Γ 15% (or 20% if high income) if held > 1 year
STCG Tax = Taxable Gain Γ Ordinary Rate if held β€ 1 year
Exclusion Fraction = Qualifying Months / 24
Partial Exclusion = Full Exclusion Γ Exclusion Fraction
($250K single Γ fraction, or $500K MFJ Γ fraction)
Taxable Gain = max(0, Realized Gain β Partial Exclusion)
LTCG Tax = Taxable Gain Γ 15% (or 20% if high income) if held > 1 year
STCG Tax = Taxable Gain Γ Ordinary Rate if held β€ 1 year
Example
$200K gain, single, 15 months owned and used, job change qualifying reason:
Exclusion fraction: 15/24 = 62.5% | Partial exclusion: $250,000 Γ 62.5% = $156,250
Taxable gain: $200,000 β $156,250 = $43,750
LTCG tax (15%): $43,750 Γ 15% = $6,563
Tax without partial exclusion: $200,000 Γ 15% = $30,000 β save $23,437!
Exclusion fraction: 15/24 = 62.5% | Partial exclusion: $250,000 Γ 62.5% = $156,250
Taxable gain: $200,000 β $156,250 = $43,750
LTCG tax (15%): $43,750 Γ 15% = $6,563
Tax without partial exclusion: $200,000 Γ 15% = $30,000 β save $23,437!
Extended
Date-Based Ownership Calculator with IRS Safe-Harbor Checklist
Enter exact start/end dates. Calculate ownership and use months precisely. Apply IRS safe-harbor tests for each qualifying reason. See tax owed curve by months owned.
Enter exact dates to calculate ownership and use months. The IRS safe-harbor checklist helps verify your qualifying reason. Chart shows tax owed across all possible months-owned scenarios.
Date-Based Ownership Calculator
IRS Safe-Harbor Checklist
| Category | Qualifying Condition | Applies? |
|---|---|---|
| Job Change | New workplace β₯50 miles farther from home than old workplace | |
| Health | Doctor certified need to relocate for health of you or family member | |
| Death | Death of co-owner or family member requiring move | |
| Divorce | Divorce or legal separation after date of purchase | |
| Multiple Births | 2+ children born/adopted from same pregnancy within 2 years | |
| Condemnation | Home destroyed or condemned through no fault of taxpayer | |
| Involuntary | Military, intelligence, or Foreign Service duty |
Tax Owed by Months Owned (1β24 months, $200K gain, single)
Exclusion Comparison Table
| Scenario | Exclusion | Taxable Gain | LTCG Tax |
|---|
Frequently Asked Questions
What are the qualifying reasons for a partial Β§121 exclusion?
The IRS allows a partial exclusion when the home is sold before meeting the full 2-year use-and-ownership test if there is a "qualifying unforeseen circumstance." The IRS safe harbors include: (1) Job change β new workplace must be at least 50 miles farther from the old home than the old job was. (2) Health β doctor recommended move, or need to care for a family member. (3) Death, divorce, or legal separation. (4) Qualified birth or adoption β 2+ children born or adopted within 2 years. (5) Other unforeseen circumstances β job loss, natural disasters. The partial exclusion is pro-rated based on months of ownership and use vs 24 months.
How is the partial Β§121 exclusion calculated?
The partial exclusion is: Qualifying Fraction Γ Full Exclusion Amount. The qualifying fraction equals the shorter of: months of ownership or months of use during the 5-year look-back period, divided by 24. For example, if you owned and lived in the home for 12 months with a qualifying reason, the fraction is 12/24 = 50%. For a single filer, the partial exclusion is 50% Γ $250,000 = $125,000. Any gain above the partial exclusion is taxable as long-term capital gain (if held > 1 year) or short-term (if held β€ 1 year).
What is the difference between the ownership test and use test for Β§121?
The ownership test requires you to have owned the home for at least 24 months (2 years) out of the 5-year period ending on the sale date. The use test requires you to have used the home as your principal residence for at least 24 months out of the same 5-year period. Both tests must normally be met for the full exclusion. However, the ownership and use months do not need to be the same months β they just each need to add up to at least 24 months total. For the partial exclusion, months of ownership and use are counted separately and the lesser controls the fraction.
Can I use Β§121 if I already used it in the past 2 years?
No. The Β§121 exclusion can only be used once every 2 years. If you excluded gain from a home sale in the past 2 years, you cannot use it again β not even the partial exclusion. The only exception is if the current sale qualifies due to an unforeseen circumstance that would have made selling the prior home impossible. This rule primarily affects serial home flippers or people who move frequently.
Does the Β§121 exclusion apply to home offices?
If you have been claiming home office deductions (Schedule C or Form 8829), the portion of the home used as office space is not eligible for the Β§121 exclusion. You must allocate gain between the residential portion (eligible for Β§121) and the office portion (taxable, potentially subject to Β§1250 depreciation recapture). The office portion gain is treated as an unrecaptured Β§1250 gain taxed at 25%. For this reason, some homeowners choose not to claim home office deductions to preserve the full Β§121 exclusion.