E&P Depreciation Rules: ADS, Bonus Add-Back, and Section 179

The Earnings and Profits depreciation rules require corporations to run a second depreciation schedule alongside the one used for taxable income. For tangible personal property placed in service after 1986, IRC Section 312(k) forces E&P depreciation to be computed under the Alternative Depreciation System (ADS), using the straight-line method over the ADS recovery period, with bonus depreciation disregarded and Section 179 expense spread ratably over five years.¹ Every difference between the two schedules becomes an adjustment that raises or lowers E&P for the year, which in turn decides how much of any shareholder distribution is a taxable dividend.

Why the Two Depreciation Systems Exist

E&P is meant to measure a corporation’s real economic capacity to pay dividends, not its taxable income. If MACRS deductions counted for E&P, a corporation could buy equipment, claim a large first-year write-off, drive E&P to zero, and send cash to shareholders as a tax-free return of capital instead of a taxable dividend. Section 312(k) closes that door by requiring a slower depreciation method for E&P purposes.

The total depreciation over an asset’s life is the same under both systems. Only the timing changes. Early in the asset’s life, the MACRS deduction on the tax return exceeds the ADS deduction, so E&P sits above taxable income. Later, the relationship reverses, and ADS deductions continue after MACRS has run out.

Calculating ADS Depreciation for E&P

The ADS calculation takes three inputs: the asset’s full cost basis, the straight-line method, and the ADS recovery period. No accelerated methods. No declining balance. No bonus. Divide the depreciable basis evenly across the ADS recovery period, applying the same half-year or mid-quarter convention used under regular MACRS in the first and last years.²

Each year, compare the MACRS deduction claimed on the return against the ADS straight-line deduction for the same asset. The difference is the E&P adjustment. In early years, MACRS is larger, so the difference is added back to increase E&P. In later years, the ADS deduction can exceed what remains of MACRS, producing a negative adjustment that decreases E&P. Every depreciable asset needs both schedules tracked for the full recovery period.

ADS Recovery Periods Compared to GDS

How large the annual adjustment gets depends on how far apart the ADS recovery period sits from the General Depreciation System (GDS) period. Common examples:²

Computers and peripherals: 5 years GDS, 5 years ADS
Automobiles and light trucks: 5 years GDS, 5 years ADS
Office furniture: 7 years GDS, 10 years ADS
General-purpose personal property with no assigned class life: 7 years GDS, 12 years ADS
Residential rental property: 27.5 years GDS, 30 years ADS
Nonresidential real property: 39 years GDS, 40 years ADS

For computers and vehicles, the periods match, so the E&P adjustment comes entirely from the shift to straight-line, not from a longer life. Office furniture and general-purpose equipment take both a slower method and a longer period, producing much larger early-year adjustments. Real estate already uses straight-line under GDS with a similar recovery period, so its annual E&P difference stays small. Property with no specific class life defaults to 12 years for personal property and 40 years for certain real property.²

Bonus Depreciation Add-Back

Bonus depreciation drives the largest E&P adjustments for equipment-heavy corporations. Under the One Big Beautiful Bill Act enacted in 2025, 100% bonus depreciation was permanently restored for qualified property acquired after January 19, 2025, replacing the phase-down that had reduced the percentage to 80% in 2023, 60% in 2024, and 40% in 2025 before the new law took effect.³ The IRS has confirmed businesses can deduct 100% of the cost of qualifying property in the first year it is placed in service.⁴

None of that carries over to E&P. Because Section 312(k)(3)(A) requires ADS for all tangible property under Section 168, bonus depreciation is completely disregarded when computing E&P.¹ The mechanical steps:

Add back the full amount of bonus depreciation claimed on the return.
Depreciate the asset’s full cost using ADS straight-line over the ADS recovery period.
Subtract the annual ADS deduction from E&P each year.

A corporation buys $200,000 of manufacturing equipment and claims 100% bonus depreciation on its return. For E&P, it adds back $200,000, then deducts $16,667 per year over a 12-year ADS life. In year one, E&P is $183,333 higher than taxable income from that asset alone. The gap unwinds slowly across the remaining 11 years, when ADS deductions continue and the MACRS deduction is already used up.

Section 179 Spread Over Five Years

Section 179 lets corporations expense qualifying property immediately. For 2026, the maximum Section 179 deduction is $2,560,000, with a phase-out beginning at $4,090,000 in total qualifying property placed in service during the year.

For E&P, Section 179 follows its own rule that departs from the general ADS requirement. Under IRC Section 312(k)(3)(B), any amount deducted under Section 179 must be spread ratably over five years for E&P, starting with the year the property is placed in service.¹ The five-year period applies regardless of the asset’s actual ADS recovery period. Equipment with a 12-year ADS life still gets a five-year E&P write-off if it was expensed under Section 179.

A corporation claims $100,000 in Section 179 on its return. For E&P, it adds back $100,000 and deducts $20,000 per year for five years. The net year-one E&P increase is $80,000. By the end of year five, the two systems are back in sync for that asset. The same five-year rule applies to amounts deducted under Sections 179B, 179C, 179D, and 179E, with a narrow exception for real estate investment trusts claiming energy-efficient building deductions under Section 179D.¹

A Worked Example

A corporation earns $500,000 in taxable income and places two assets in service:

Asset A: office furniture, $70,000 cost, 100% bonus depreciation claimed on the return, 10-year ADS recovery period.
Asset B: equipment, $100,000 cost, Section 179 claimed on the return, five-year E&P amortization.

The return already reflects $170,000 in deductions from these two assets. For E&P:

Asset A: add back $70,000 of bonus depreciation, subtract $7,000 in ADS straight-line ($70,000 ÷ 10 years). Net E&P increase: $63,000.
Asset B: add back $100,000 of Section 179, subtract $20,000 for the five-year amortization ($100,000 ÷ 5). Net E&P increase: $80,000.

Total depreciation adjustment: positive $143,000. Current E&P is $500,000 plus $143,000, or $643,000 before any non-depreciation adjustments. Even though taxable income was $500,000, up to $643,000 of distributions could be classified as taxable dividends. In later years, the ADS and Section 179 amortization deductions continue reducing E&P after the return deductions are fully used, gradually unwinding the difference.

How the Adjustment Reaches Shareholders

IRC Section 316 defines a dividend as any distribution made out of current or accumulated E&P.⁵⁶⁷

Current E&P is calculated first, at the close of the tax year, including every depreciation adjustment. If current E&P is positive and covers the distribution, the entire amount is a dividend, even if accumulated E&P is negative. If current E&P falls short, the remaining distribution draws from accumulated E&P.

This is where the depreciation add-back becomes real money. A corporation using aggressive bonus depreciation and Section 179 will show low taxable income but substantially higher E&P because of the mandatory add-backs. More E&P means more of each distribution is taxed as a dividend. Shareholders expecting a tax-free return of capital may instead owe tax at ordinary or qualified dividend rates. The corporation’s depreciation choices on its own return effectively set the tax treatment on every shareholder’s personal return.

Reporting and Recordkeeping

Corporations that make nondividend distributions, meaning distributions that exceed E&P and are treated as returns of capital, must file Form 5452, Corporate Report of Nondividend Distributions, with the IRS.⁸ Calendar-year corporations attach Form 5452 to the return for the year the nondividend distributions were made. Fiscal-year corporations attach it to the return due for the first fiscal year ending after the calendar year of the distributions.⁹

Filing the form requires a completed E&P computation, which requires the parallel ADS depreciation schedules to have been maintained year over year for every depreciable asset. A corporation that never tracked E&P depreciation separately may not discover the error until an IRS examination reclassifies distributions the shareholders reported as returns of capital into taxable dividends, triggering back taxes, interest, and accuracy-related penalties at the shareholder level.

1
Office of the Law Revision Counsel. 26 U.S. Code 312 – Effect on Earnings and Profits
2
Internal Revenue Service. Publication 946 – How to Depreciate Property
3
Office of the Law Revision Counsel. 26 U.S. Code 168 – Accelerated Cost Recovery System
4
Internal Revenue Service. One, Big, Beautiful Bill Provisions
5
Office of the Law Revision Counsel. 26 USC 316 – Dividend Defined
6
Office of the Law Revision Counsel. 26 U.S. Code 301 – Distributions of Property
7
Internal Revenue Service. Topic No. 404, Dividends and Other Corporate Distributions
8
Internal Revenue Service. About Form 5452, Corporate Report of Nondividend Distributions
9
Internal Revenue Service. Form 5452 – Corporate Report of Nondividend Distributions