100% Bonus Depreciation Is Permanent — But Your 2026 Deduction Still Has a Clock

Aircraft logbook with fountain pen and June 2026 desk calendar on a wooden desk, with a business jet silhouette in a hangar at golden hour — OakTree Aviation Services.

Part 1 of a 3-part series on planning a business aircraft acquisition in 2026.

By Richard "Rick" Rossner, CEO, OakTree Aviation Services LLC | Senior Certified Aircraft Appraiser

A note on tax guidance. The rules discussed below reflect the One Big Beautiful Bill Act (OBBBA) of 2025 and IRS Notice 2026-11, which is interim guidance issued in January 2026 and still subject to formal regulations. Nothing in this article is tax advice. Every prospective buyer should review their specific facts with a qualified aviation tax attorney or CPA before relying on any depreciation strategy.

The mid-year reality

We are at the halfway point of fiscal 2026. For business owners and operators who have been quietly thinking about acquiring an aircraft this year, the calendar — not the tax code — is now the most underestimated variable in the decision.

The reason is simple. To claim bonus depreciation for the 2026 tax year, the aircraft must be placed in service by December 31, 2026. That is not the date you sign a Letter of Intent. It is not the date you wire a deposit. It is the date the aircraft is actually available for use in your trade or business.

A serious business aircraft acquisition — done correctly, with proper diligence — typically runs three to six months from search to closing. Run that math against the calendar, and June is not early. June is on time.

What the law actually says today

For several years, business aircraft buyers have been operating under a moving target. The Tax Cuts and Jobs Act of 2017 phased bonus depreciation down from 100% toward zero, and 2026 was previously scheduled to allow only 20% under the prior framework.

That changed

The One Big Beautiful Bill Act, signed July 4, 2025, permanently restored 100% bonus depreciation for qualifying new and used aircraft acquired and placed in service on or after January 20, 2025. There is no longer a phaseout looming over your decision.

In January 2026, the IRS issued Notice 2026-11, providing interim guidance on how taxpayers should apply the existing Section 168(k) framework under the new permanent rules. The notice clarifies acquisition dates, placed-in-service rules, and available elections. Until formal regulations are issued, taxpayers may rely on this interim guidance.

The headline is straightforward. The deduction is permanent. The qualification rules are not relaxed. And the calendar still controls the year you can claim it.

Why June matters operationally

A defensible aircraft acquisition is not a transaction. It is a process. A reasonable timeline for a mid-size business aircraft generally includes:

• Needs analysis. Mission profile, range, payload, runway requirements, ownership structure, and financing posture.

• Market search and comparables. Identifying realistic candidates, screening logbooks and damage history, and developing a defensible offer range.

• Letter of Intent and deposit. Negotiated commercial terms before deeper diligence.

• Pre-buy inspection. Coordinated at a qualified facility, often requiring scheduling weeks in advance.

• Independent appraisal. Particularly important for financing, collateral review, or any transaction with a fiduciary or institutional dimension.

• Closing, registration, and placed-in-service documentation. Title work, escrow, FAA registration, and the records that substantiate the in-service date.

Each step has its own lead time. Compress them, and quality suffers. Skip them, and the IRS audit risk on a six- or seven-figure deduction increases sharply.

A buyer who begins serious work in June is positioning for a Q4 close. A buyer who begins in October is, in most cases, betting on a 2027 placed-in-service date.

The qualification traps

Permanent does not mean automatic. The same rules that have always governed business aircraft depreciation still apply, and they remain the most common source of recapture and audit exposure.

At a minimum, prospective buyers should understand:

• Predominant business use. The aircraft must generally be used more than 50% for qualified business use, with a 25% threshold under Section 280F's "listed property" rules.

• Predominantly U.S. use. The aircraft must be used predominantly within the United States.

• No prior taxpayer use. The taxpayer cannot have previously owned, leased, or chartered the aircraft.

• Ongoing compliance. These tests apply not only in the year of acquisition but throughout the recovery period. Failing a subsequent year can trigger recapture of previously claimed depreciation.

These are not edge cases. They are the rules under which an aircraft deduction succeeds or fails in audit. Documentation discipline — flight logs, mission purpose, passenger manifests — matters as much as the purchase itself.

We will cover these qualification rules in detail in Part 3 of this series.

Where OakTree fits

OakTree Aviation Services LLC is an independent aircraft appraisal and aviation consulting firm. We provide impartial, defensible, well-documented analysis for bank financing, collateral review, estates and trusts, IRS-related work, and legal or fiduciary contexts.

For buyers planning a 2026 acquisition, we serve two roles:

1. USPAP-compliant appraisal for financing, collateral, and defensible valuation documentation.

2. Buyer's agent representation — needs analysis, market search, comparable research, LOI support, pre-buy inspection coordination, negotiation, and management through closing and registration.

We are California-based, strongly positioned for California and the Western U.S., and available for nationwide and international assignments when scope, aircraft value, and complexity support the engagement. Meeting facilities are available by appointment in Burbank, with on-site inspections performed at the aircraft's location.

Part 2 of this series will walk through the buyer's agent engagement in detail.

If you are considering a 2026 acquisition

The deduction is permanent. The window for the 2026 tax year is not. If June feels early, the timeline says otherwise.

To discuss a potential engagement, visit oaktreeaviation.com/buyers-agent or contact our office directly through oaktreeaviation.com.

Richard "Rick" Rossner, CEO, OakTree Aviation Services LLC | Senior Certified Aircraft Appraiser