Federal Solar ITC (Section 48) Dual-Use Property Depreciation Recapture Calculator
Calculate the depreciation recapture owed when selling or converting Section 48 dual-use solar property within the 5-year recapture window. This tool handles agrivoltaics, solar carports, landfill solar, and floating solar with cost basis allocation. For recapture on home office-to-personal use conversions, see our Solar Tax Credit Recapture Calculator.
📘 View Step-by-Step Calculation
Disclaimer: This calculator provides estimates for educational purposes only. Actual tax liabilities depend on your specific situation. Consult a qualified tax professional for definitive guidance. IRS Form 4255 and Form 4797 are the official IRS forms for reporting recapture.
Instant Answer Table: Section 48 Recapture Scenarios
See how different scenarios affect your Section 48 recapture liability. These examples show real-world calculations for dual-use solar property under the 5-year recapture period.
| Scenario | Cost Basis | Energy % | Years Held | ITC Claimed | Recapture % | Recapture Amount | Net Liability |
|---|---|---|---|---|---|---|---|
| Solar Carport 80% Energy | $1,000,000 | 80% | 2 years | $240,000 | 80% | $192,000 | $212,000 |
| Agrivoltaic Farm 70% Energy | $2,500,000 | 70% | 1 year | $525,000 | 100% | $525,000 | $725,000 |
| Landfill Solar 90% Energy | $5,000,000 | 90% | 3 years | $1,350,000 | 60% | $810,000 | $860,000 |
| Floating Solar 85% Energy | $3,200,000 | 85% | 4 years | $816,000 | 40% | $326,400 | $406,400 |
| 80/20 Rule Qualified 80% Energy ✅ Full ITC | $1,000,000 | 80% | 5+ years | $240,000 | 0% | $0 | $0 |
| Non-Qualified Structure 50% Energy ⚠️ Partial | $750,000 | 50% | 2 years | $112,500 | 80% | $90,000 | $152,500 |
Notes: ITC claimed = Energy Basis × 30%. Recapture % based on years held (1-5). Net liability includes recapture + taxable gain on sale. All values are estimates for educational purposes.
💡 Key Insight: Holding dual-use solar property for 5+ years eliminates recapture entirely. The 80/20 Rule allows full ITC qualification if ≥80% of basis is energy property.
What the Results Mean for Your Section 48 Dual-Use Property
After running your calculation, you'll see four key numbers that tell the complete story of your recapture liability.
Recapture Amount
The amount of Investment Tax Credit you must repay. This increases the longer you wait — up to 100% in Year 1, dropping to 20% by Year 5. After 5 years, recapture drops to $0.
Net Tax Liability
Your total tax hit: recapture amount plus any taxable gain from the sale. If you sold at a loss, this may be lower than the recapture amount alone.
ITC Originally Claimed
30% of your energy basis. This is the total tax credit you received when the property was placed in service. The recapture amount is a percentage of this number.
Recapture Percentage
Based on how many years you held the property. Year 1 = 100%, Year 2 = 80%, Year 3 = 60%, Year 4 = 40%, Year 5 = 20%, Year 5+ = 0%.
⚠️ Important: These results are estimates for educational purposes only. Your actual tax liability depends on your specific facts and circumstances. Always consult a qualified tax professional for definitive guidance.
How to Use This Calculator: Step-by-Step
This calculator determines your Section 48 recapture liability when selling or converting dual-use solar property within the 5-year recapture window. Follow these steps to get accurate results.
- Enter the Total Cost Basis. The original total cost of the dual-use property, including solar equipment, installation, and any dual-use structures (carport, agricultural infrastructure).
- Enter Depreciation Claimed to Date. The total depreciation deductions you've taken on the energy property under MACRS since placing it in service.
- Enter the Sale or Disposal Price. The amount received from selling the property, or the fair market value if converting to a non-qualifying use.
- Select the Year Placed in Service. This determines how many years you've held the property — critical for the recapture percentage.
- Adjust the Energy Allocation Slider. Set the percentage of total cost basis allocated to energy-generating equipment. Non-energy structures (agricultural buildings, parking decks) reduce your ITC basis.
- Click "Calculate Recapture." View your recapture amount, net tax liability, and step-by-step breakdown instantly.
What Is Section 48 Dual-Use Property?
Section 48 dual-use property refers to solar energy installations that serve both energy generation and another functional purpose. The Investment Tax Credit (ITC) applies to the energy-generating portion of the property, but recapture rules apply when the property is disposed of or changes use within 5 years.
Common Types of Dual-Use Property
- Agrivoltaics (Solar + Agriculture) Solar panels installed above crops or grazing land. The land produces both energy and agricultural products.
- Solar Carports (Solar + Parking) Solar panels mounted on parking lot canopies, generating energy while providing shade and weather protection for vehicles.
- Solar on Landfills (Solar + Brownfield Reuse) Solar installations on closed landfills or brownfield sites, converting non-productive land into energy-generating assets.
- Floating Solar (Solar + Water Management) Solar panels mounted on floating platforms on reservoirs, ponds, or other water bodies — combining energy generation with water conservation.
Why Dual-Use Matters for the ITC
Under Section 48, only the energy-generating portion of a project qualifies for the ITC. This means you must allocate your total cost basis between:
- Energy Property: Solar panels, inverters, mounting systems, electrical equipment — eligible for ITC.
- Non-Energy Property: Structures, landscaping, fencing, agricultural equipment — NOT eligible for ITC.
The allocation directly affects your ITC amount and subsequent recapture liability. This is why the Energy Allocation Slider in the calculator is so important. For a more precise allocation backed by engineering analysis, consider commissioning a cost segregation study, which can identify all qualifying energy components and often reveals a higher energy allocation than simplified estimates.
Example: Agrivoltaic Farm
A $2M agrivoltaic project with $1.4M in solar equipment and $600K in agricultural infrastructure = 70% energy allocation.
- ITC claimed: $1.4M × 30% = $420,000
- If sold in Year 2: 80% recapture = $336,000
- Net benefit retained: $420,000 − $336,000 = $84,000
The 80/20 Rule — A Critical Exception
Under the 80/20 Rule, if at least 80% of your total cost basis is energy property, the entire project qualifies for the ITC. This is a significant benefit for dual-use projects with a high percentage of energy equipment.
✅ Qualifies for 80/20 Rule
$1,000,000 total cost
Energy basis: $820,000 (82%)
Non-energy basis: $180,000 (18%)
ITC claimed: $300,000 (30% of total)
❌ Does NOT Qualify
$1,000,000 total cost
Energy basis: $720,000 (72%)
Non-energy basis: $280,000 (28%)
ITC claimed: $216,000 (30% of energy basis only)
Key Takeaway
The energy allocation percentage directly impacts both your initial ITC benefit and your recapture liability. Accurate allocation is essential for tax planning and compliance.
The 5-Year Recapture Period: How It Works
Section 48 recapture applies during a 5-year period starting from the date your dual-use solar property is placed in service. If you dispose of the property or change its use within this window, a portion of the ITC must be repaid.
The recapture percentage decreases the longer you hold the property, creating a strong incentive to maintain qualifying use for at least 5 years.
Recapture Percentage by Year
| Years Held | Recapture Percentage | ITC Retained | Risk Level |
|---|---|---|---|
| Less than 1 year | 100% | 0% | 🔴 High |
| 1 to 2 years | 80% | 20% | 🔴 High |
| 2 to 3 years | 60% | 40% | 🟡 Medium |
| 3 to 4 years | 40% | 60% | 🟡 Medium |
| 4 to 5 years | 20% | 80% | 🟢 Low |
| 5+ years | 0% | 100% | ✅ Zero |
Example: A $1M solar carport with 80% energy basis = $240,000 ITC claimed.
- Year 1 sale: Recapture = $240,000 × 100% = $240,000 (repay everything)
- Year 3 sale: Recapture = $240,000 × 60% = $144,000 (keep $96,000)
- Year 5+ sale: Recapture = $240,000 × 0% = $0 (keep everything)
What Counts as "Placed in Service"?
The placed-in-service date is the day the solar property is ready and available for its intended use — generating electricity. For dual-use property, this means the solar equipment must be operational and producing energy, even if the agricultural or parking components aren't fully complete.
- For agrivoltaics: The solar panels must be generating power, even if crops aren't planted yet.
- For carports: The solar system must be producing energy, even if the parking lot isn't fully paved.
- For landfill solar: The solar installation must be operational, even if landscaping isn't finished.
The placed-in-service date starts the 5-year recapture clock. Use the Year Placed in Service dropdown in the calculator to set this date.
What Triggers Recapture Under Section 48?
Recapture is triggered when your dual-use solar property is disposed of or changes use before the 5-year recapture period ends. Understanding these triggers helps you plan and avoid unexpected tax bills.
Disposition Triggers
- Sale or Transfer Selling the dual-use property to a third party. Most transfers trigger recapture, with limited exceptions for transfers between spouses or related parties.
- Foreclosure or Repossession If the property is repossessed by a lender, the taxpayer is treated as having disposed of the property.
- Exchange or Like-Kind Exchange Section 1031 exchanges may trigger recapture unless the replacement property continues to qualify as Section 48 energy property.
Change in Use Triggers
- Cessation of Agricultural Activity For agrivoltaic projects, if you stop farming the land while keeping the solar installation, this may constitute a change in use triggering partial recapture.
- Conversion to Single-Use Converting dual-use property to single-use (e.g., removing crops or parking structures) may change the energy allocation percentage and trigger recapture.
- Removal of Energy Equipment Removing or significantly reducing the solar equipment that generated the ITC can trigger recapture on the proportion of energy property removed.
- Change in Ownership Structure Partnership or corporate structure changes may trigger recapture if the new entity doesn't qualify for the ITC under the same terms.
What Does NOT Trigger Recapture?
- Normal wear and tear — Routine maintenance and repairs don't trigger recapture.
- Casualty loss — Property destroyed by fire, storm, or other casualty may be exempt from recapture if properly documented.
- Transfer between spouses — Transfers to a spouse (or from a spouse to a taxpayer) generally don't trigger recapture under Section 1041.
- Death of taxpayer — Transfers to heirs at death may avoid recapture.
✅ Generally Safe
- Holding 5+ years
- Routine maintenance
- Spousal transfers
- Inheritance
⚠️ Recapture Risk
- Sale within 5 years
- Converting dual-use to single-use
- Removing energy equipment
- Foreclosure or repossession
Key Takeaway
Disposition and change in use are the primary recapture triggers. Careful planning around ownership structure, use classification, and holding period can significantly reduce or eliminate your recapture liability.
Real-World Scenarios: Section 48 Recapture in Action
These real-world scenarios show how Section 48 recapture plays out in different dual-use property situations. Each example walks through the allocation, ITC claimed, and recapture calculation.
Scenario 1: Agrivoltaic Sheep Farm — Sold in Year 2
Analysis: The farm was sold after only 2 years, triggering 80% recapture. The farmer lost $234,000 of the $292,500 ITC benefit — a significant hit. If the farm had been held for 5+ years, the full $292,500 would have been retained.
Scenario 2: Solar Carport — Held 4 Years
Analysis: Holding for 4 years reduced recapture to 40%, retaining $122,400 of the $204,000 ITC. The carport owner had a modest gain on sale, adding to the total tax liability. Holding one more year would have eliminated recapture entirely.
Scenario 3: Landfill Solar — 80/20 Rule Qualified
Analysis: With 82% energy allocation, the project qualified for the 80/20 Rule — the entire $4M project received the ITC. Held for 6 years, the recapture period expired, so the full $1.2M ITC was retained. Only the gain on sale ($300,000) was taxable.
Key Takeaway from These Scenarios
The combination of energy allocation percentage and holding period determines your recapture exposure. Higher energy allocation (especially ≥80%) and longer holding periods minimize recapture liability. The best outcome is holding 5+ years with ≥80% energy allocation.
Tax Planning Strategies to Minimize Section 48 Recapture
Smart tax planning can significantly reduce or eliminate your Section 48 recapture exposure. Here are proven strategies for dual-use solar property owners.
Strategy 1: Hold for 5+ Years
The simplest and most effective strategy. After 5 years, recapture drops to zero. If you can hold your dual-use property for at least 5 years from the placed-in-service date, you retain the full ITC benefit.
- For agrivoltaics: Structure long-term leases (10+ years) with farmers to ensure continued agricultural use.
- For carports: Align with long-term parking agreements or property ownership.
- For landfill solar: Landfill closure periods often extend beyond 5 years naturally.
Strategy 2: Target ≥80% Energy Allocation
The 80/20 Rule is a powerful tool. By designing projects with at least 80% of total cost basis in energy equipment, the entire project qualifies for ITC — including non-energy components.
Strategy 3: Use Partnerships or LLC Structures
Transfers of property interests between related parties may avoid recapture. Consider holding dual-use property in a partnership or LLC to allow ownership changes without triggering disposition.
- Partnerships: Section 50(d) provides special rules for partnership recapture.
- S-Corps: Shareholder transfers may be structured to avoid recapture.
- LLCs: Member interest transfers can be managed without disposition.
⚠️ Consult a tax professional before structuring any entity-based strategy — the rules are complex and fact-specific.
Strategy 4: Monitor "Change in Use" Carefully
Change in use triggers can be subtle. Maintain active dual-use status for the entire 5-year period.
- For agrivoltaics: Maintain agricultural activity every season, even if minimal. Document farming operations with photos, receipts, and records.
- For carports: Keep parking areas operational and accessible. Don't convert to storage or other non-parking uses.
- For landfill solar: Avoid removing or significantly altering the landfill cap or cover during the recapture period.
Strategy 5: Consider Section 1031 Exchanges
A Section 1031 like-kind exchange may allow you to defer recapture by exchanging your dual-use solar property for similar property. However, the replacement property must continue to qualify as Section 48 energy property.
Strategy 6: Document Everything
The IRS may audit recapture calculations. Maintaining thorough documentation protects you if challenged.
- Cost basis records: Invoices, contracts, and allocation documentation.
- Placed-in-service date: Proof of when the system became operational (date of first interconnection, utility PTO).
- Use documentation: Photos, lease agreements, and operational records showing dual-use status.
- Depreciation records: Form 4562 and supporting depreciation schedules.
Pre-Installation Planning
- Design for ≥80% energy allocation
- Structure ownership for flexibility
- Document dual-use intent
During the Recapture Period
- Hold for 5+ years
- Maintain dual-use status
- Document use annually
Exit Planning
- Wait until Year 5+ to sell
- Consider 1031 exchange
- Consult tax professional
Key Takeaway
The most effective recapture avoidance strategy is simple: hold for 5+ years and maintain dual-use status. If you must sell, use the calculator to estimate your exposure and plan accordingly with professional guidance.
Why This Calculator Is Different: The Dual-Use Advantage
Most solar tax calculators treat all projects the same. This one doesn't. Built specifically for Section 48 dual-use property, it addresses the unique challenges of agrivoltaics, solar carports, landfill solar, and floating solar installations.
Built for Dual-Use Property
Generic calculators ignore the basis allocation problem. This tool lets you split costs between energy and non-energy components — the critical first step for any dual-use project.
80/20 Rule Integration
The 80/20 Rule is a game-changer for dual-use property. Our calculator shows you exactly where you stand — and what happens if you cross the 80% threshold.
Step-by-Step Transparency
No black boxes. Every calculation is shown step-by-step, so you understand exactly how your recapture amount was determined. This builds trust and helps with tax planning.
Real-World Scenarios
Not just theory. Our examples use real-world scenarios — agrivoltaic sheep farms, solar carports, landfill projects — so you can see how the math works in practice.
How We Stack Up Against Generic Calculators
Built for Real-World Dual-Use Projects
Whether you're a farmer adding solar to grazing land, a developer building a solar carport, or a municipality converting a landfill to energy production — this calculator is designed for your specific needs. Generic calculators won't cut it. This one will.
Try it now. Enter your numbers and see exactly how much recapture you'll face — and what you can do to minimize it.
Frequently Asked Questions: Section 48 Dual-Use Property Recapture
Section 48 dual-use property refers to solar energy installations that serve both energy generation and another functional purpose, such as agriculture (agrivoltaics), parking (solar carports), or brownfield redevelopment (landfill solar). The Investment Tax Credit (ITC) applies to the energy-generating portion of the property, but recapture rules apply when the property is disposed of or changes use within 5 years.
Depreciation recapture under Section 48 occurs when you dispose of or convert dual-use solar property within 5 years of placing it in service. The recapture amount is calculated as: (ITC claimed) × (recapture percentage based on years held). The recapture percentage decreases from 100% in Year 1 to 0% after 5 years. The recaptured amount must be reported as additional tax on your return.
The 80/20 Rule under Section 48 states that if at least 80% of the total cost basis of a project is energy property, the entire project qualifies for the ITC. This is critical for dual-use property where only part of the project is energy-generating. If you cross the 80% threshold, non-energy components become eligible for the ITC as well. Our calculator shows you exactly where you stand relative to this threshold.
The Section 48 recapture period is 5 years from the date the property is placed in service. If you dispose of the property or it ceases to qualify as energy property within this 5-year window, a portion of the ITC must be recaptured. The recapture percentage is: 100% in Year 1, 80% in Year 2, 60% in Year 3, 40% in Year 4, 20% in Year 5, and 0% after 5 years.
Recapture is triggered when dual-use solar property is sold, disposed of, or when its use changes so that it no longer qualifies as energy property within the 5-year recapture period. Key triggers include: sale or transfer to a third party, foreclosure or repossession, cessation of agricultural activity (for agrivoltaics), conversion from dual-use to single-use, and removal of energy equipment. Even partial changes can trigger proportionate recapture.
Basis allocation for dual-use property requires splitting the total cost between energy-generating property (which qualifies for ITC) and non-energy property (which does not). Energy property includes solar panels, inverters, racking, and electrical equipment. Non-energy property includes structures, landscaping, fencing, and agricultural equipment. This allocation directly affects your ITC amount and subsequent recapture calculations. Our Energy Allocation Slider helps you determine the right split.
Section 48 provides the Investment Tax Credit (ITC) — a 30% credit based on the cost basis of the energy property. Section 45 provides the Production Tax Credit (PTC) — a per-kilowatt-hour credit based on energy produced over 10 years. Recapture rules differ between the two: Section 48 recapture applies during the 5-year recapture period, while Section 45 recapture applies if the facility ceases to qualify for the PTC. Most commercial solar projects choose the ITC (Section 48) because it provides an upfront benefit. For residential solar recapture (home office to personal use conversions), see our Solar Tax Credit Recapture Calculator.
Section 48 recapture is reported on Form 4797 (Sales of Business Property). The recapture amount is calculated using Form 4255 (Recapture of Investment Credit). Our calculator provides the recapture amount you'll need to enter on these forms. The recaptured amount is treated as ordinary income and added to your tax liability for the year. We recommend working with a tax professional to ensure proper reporting.
Transfers of dual-use solar property can sometimes avoid recapture if the transfer meets specific IRS exceptions. Transfers between spouses (under Section 1041) generally don't trigger recapture. Transfers between related parties may also avoid recapture in certain circumstances. However, most transfers — including sales to third parties, foreclosure, and like-kind exchanges that don't preserve Section 48 qualification — trigger recapture. Always consult a tax professional for your specific situation.
For agrivoltaic projects, a "change in use" occurs when the agricultural activity ceases while the solar installation continues. This may trigger partial recapture because the property no longer qualifies as dual-use, potentially affecting the ITC percentage. For example, if you stop grazing sheep under solar panels but keep the solar system operating, the property may no longer qualify for the same ITC treatment. The recapture would be proportionate to the change in use. Maintain agricultural activity throughout the 5-year recapture period to avoid this risk.
If you sell dual-use solar property in Year 2 of the recapture period, the recapture percentage is 80%. This means you'll need to repay 80% of the ITC you originally claimed. For example, if you claimed $100,000 in ITC, you would recapture $80,000. The remaining $20,000 (20%) is retained. Year 1 sales trigger 100% recapture (repay everything), Year 3 is 60%, Year 4 is 40%, Year 5 is 20%, and after 5 years, 0%.
This calculator provides estimates for educational and planning purposes only. It is based on current IRS guidelines under Section 48 of the Internal Revenue Code and uses the official recapture percentages and formulas. However, actual tax liabilities depend on your specific facts and circumstances, including your tax bracket, state tax treatment, and any additional deductions or credits. Always consult a qualified tax professional for definitive guidance before filing your return.
Under IRA 2022 Section 6418, eligible taxpayers can transfer all or part of their ITC to a third party in exchange for cash. Transferring the credit does not eliminate recapture risk — the original taxpayer (transferor) remains liable for any recapture that occurs within the 5-year period if the property is disposed of or changes use. The recapture amount is calculated on the transferred portion of the credit. Always structure transfer agreements with clear recapture indemnification clauses and consult a tax professional.
Selling Renewable Energy Credits (RECs) or Solar Renewable Energy Credits (SRECs) generally does NOT trigger Section 48 recapture, because the sale of RECs is considered a disposition of a separate intangible asset, not a disposition of the energy property itself. However, if the REC sale agreement transfers substantial rights or control over the solar installation, the IRS may recharacterize the transaction. Most standard REC sales are safe, but consult a tax professional for complex REC monetization structures.
State solar tax credits are generally separate from the federal Section 48 ITC and may have their own recapture rules. If a state credit is based on the federal ITC amount (as some states do), a federal recapture event may also trigger state recapture. States with independent credit programs (e.g., California, New York, Massachusetts) have their own recapture periods and percentages. This calculator computes federal recapture only. Check your state's tax credit rules separately and consult a tax professional familiar with both federal and state treatment.
A cost segregation study can provide a detailed, engineer-supported breakdown of costs between energy property (5-year MACRS, ITC-eligible) and non-energy property (longer recovery periods, not ITC-eligible). Using a cost segregation study instead of a simplified allocation percentage can maximize your ITC by identifying all qualifying energy components, including electrical infrastructure, mounting systems, and site-specific equipment. It also provides defensible documentation in case of IRS audit. Many dual-use project owners find that cost segregation studies reveal a higher energy allocation than initially estimated.
Methodology: How This Calculator Works
Our Section 48 Dual-Use Property Depreciation Recapture Calculator is built on the official IRS rules and formulas. Here's exactly how the calculation works — so you can trust the numbers.
Energy Basis Calculation
Formula: Energy Basis = Total Cost Basis × Energy Allocation %
The total cost basis is split between energy property (solar equipment) and non-energy property (structures, fencing, agricultural infrastructure). Only the energy basis qualifies for the ITC.
ITC Claimed Calculation
Formula: ITC Claimed = Energy Basis × 30%
Section 48 provides a 30% Investment Tax Credit on the energy basis. For projects with ≥80% energy allocation, the 80/20 Rule applies — the ITC is calculated on the entire cost basis.
Years Held Calculation
Formula: Years Held = Current Year − Placed-in-Service Year
The recapture period is 5 years from the placed-in-service date. Years held are capped at 5+ (which results in 0% recapture).
Recapture Percentage Determination
Table:
- Less than 1 year: 100%
- 1 to 2 years: 80%
- 2 to 3 years: 60%
- 3 to 4 years: 40%
- 4 to 5 years: 20%
- 5+ years: 0%
Based on Treasury Regulation §1.48-1 and IRS guidance on Section 48 recapture.
Recapture Amount Calculation
Formula: Recapture Amount = ITC Claimed × Recapture Percentage
This is the amount of ITC that must be repaid to the IRS. It is treated as ordinary income and reported on Form 4255.
Net Tax Liability Calculation
Formula: Net Liability = Recapture Amount + Taxable Gain (if any)
Taxable gain is the positive difference between sale price and adjusted basis (cost basis minus depreciation claimed). The net liability represents your total tax hit from the disposition.
Data Sources & Legal References
- Internal Revenue Code (IRC) Section 48 — Investment Tax Credit for energy property
- IRC Section 50 — Recapture rules for investment credits
- Treasury Regulation §1.48-1 — Definition of energy property
- IRS Form 4255 — Recapture of Investment Credit
- IRS Form 4797 — Sales of Business Property
- IRS Publication 946 — How to Depreciate Property
- 26 USC §48 — Investment Tax Credit for energy property (view on Cornell LII)
- 26 USC §50 — Recapture rules for investment credits (view on Cornell LII)
Note: All calculations are based on 2026 tax rates and guidelines. Tax laws change — always verify current rates with the IRS or a tax professional.
Last Updated: July 2026 | Author: Shyraz Habib, Founder of AKCalc.online
⚠️ Disclaimer
This calculator provides estimates for educational and planning purposes only. It is not a substitute for professional tax advice. Your actual tax liability depends on your specific facts, circumstances, and applicable tax laws. Always consult a qualified tax professional before making tax decisions or filing returns.
About the Author: This calculator and guide were created by Shyraz Habib, Founder of AKCalc.online — a platform dedicated to building clear, accurate, and practical tax and financial calculators. Content is researched against current IRS publications, Treasury regulations, and the Internal Revenue Code.
Last Verified: July 2026 | Sources: IRS.gov, 26 USC §48, 26 USC §50, Treasury Reg. §1.48-1