Business Use of an Aircraft for Tax: The 50% Test, Flight Logs and Who Should Own the Plane

This page is for owners who will use a piston aircraft in their business and want the deductions to survive an audit. It covers the qualifying-use test itself (what counts, what does not, how to log it) and how your choice of owner and borrower affects both the test and your loan.

This page explains general federal rules as of September 2026 and is not tax or legal advice. Confirm your facts with a CPA or aviation tax attorney.

How does the more-than-50% business use test work for an aircraft?

IRC Section 280F(d)(4) classifies property "used as a means of transportation" as listed property, and that includes aircraft. Listed property that is not "predominantly used in a qualified business use", meaning used more than 50% that way, must be depreciated under the slower alternative depreciation system (ADS). It gets no bonus depreciation. Section 179 is available "only if you use the property more than 50% for business in the year you place it in service", according to IRS Publication 946.

You are tracking two different percentages:

• Qualified business use is use in your trade or business. It alone decides the more-than-50% test.
• Business plus investment use decides how much of the cost is depreciable and how much of the operating cost is deductible. Investment use (for example, flying to inspect property you hold only as an investment) counts here but not toward the 50% test. At 55% qualified business use plus 10% investment use you pass the test and depreciate 65% of basis.

The test runs every tax year. If you pass it when you place the aircraft in service and fail it later, you recapture the excess depreciation as ordinary income and switch to ADS. That calculation is shown in our aircraft depreciation guide. For aircraft, use is commonly measured in flight hours. Some advisors use another reasonable measure for particular purposes, so agree on the method with your CPA before the first flight.

What counts as qualified business use of an aircraft, and what does not?

The 25% aircraft rule. Section 280F(d)(6)(C) excludes from qualified business use any leasing to a 5% owner or related person, and any use provided as compensation to one. For aircraft, that exclusion "shall not apply ... if at least 25 percent of the total use of the aircraft during the taxable year consists of qualified business use" not described in the exclusion. The rule helps some company-owned aircraft that owners also fly personally, but applying it takes careful classification of every flight. Have your advisor confirm it, rather than assuming it applies.

Worked example: one year of flight-log math

Illustrative only. An owner of a regional contracting business logs one year in the company aircraft:

• The test passes at 60.0%, but the margin is thin. Losing 14 business hours, or adding 28 personal hours, would take the year to 50% or below.
• What an audit adjustment does: suppose an examiner reclassifies 15 hours of "client meeting" trips as entertainment because the only documented event was a dinner. Qualified business use falls to 49.3%. The year fails, and the excess depreciation from earlier years is recaptured as ordinary income.
• Operating costs follow the same percentage. On an assumed $40,000 of annual operating costs, the deductible business share at 60.0% is $24,000.

The lesson is not to manufacture business flights. A made-up trip is exactly what an examiner looks for. The lesson is to plan realistic business use with a comfortable margin, and to document every flight well enough that none of it gets reclassified.

What should an aircraft business-use log include?

Listed property falls under the strict substantiation rules of IRC Section 274(d): adequate records, or sufficient evidence corroborating your own statement. In practice that means a log kept at or near the time of each flight. A log rebuilt from memory during an audit carries little weight.

• Date, departure and arrival airports, and Hobbs or tach time for every leg, including positioning legs
• Pilot in command and every passenger, with each person's business relationship to you
• A specific business purpose: who you met, for which client, project or job number (not just "business")
• A classification for every flight: business, investment, personal, commuting or entertainment
• A pointer to corroboration: calendar invite, invoice, contract, email or site report
• For company-owned aircraft, personal flights by owners and employees, with the value reported as income where required
• A year-end summary that reconciles total hours to the Hobbs meter, fuel receipts and maintenance records

Keep the log and supporting records until the statute of limitations expires for the year you sell or otherwise dispose of the aircraft, because they support the depreciation reported in every year before that.

How are mixed-purpose trips, family passengers and personal flights treated?

• Primary purpose governs the trip. A trip made mainly for business generally keeps its business legs even if you add a personal day. A detour to a vacation spot is a personal leg.
• Family on a business flight. A spouse or child riding along does not by itself turn a business flight into a personal one for the hour count. On a company-owned aircraft, though, their seats can be a taxable fringe benefit to the employee or owner. Ask your advisor how to value and report them.
• Owner's personal flights in a company aircraft. These are generally compensation to the owner. For a 5% owner, that use is excluded from qualified business use unless the 25% aircraft rule applies, so it can push the aircraft toward the 50% line even when the income is reported correctly.

Who should own the aircraft: you, your operating company or an LLC?

The owner determines whose business the flying counts for, who is exposed to liability, and who signs the loan. Below is how the three common structures compare for a piston owner. None of them is right in every case.

The LLC route has the most moving parts: registration, citizenship, state use tax and the line between a legal lease and illegal charter. Those are covered in owning an aircraft in an LLC.

What does business use mean for your aircraft loan?

• Lenders underwrite the borrower, not the tax plan. Credit, income, liquidity and down payment drive approval. Most aviation lenders look for 680+ credit, with the best pricing typically at 720–730+, and AOPA cites a 15% minimum down payment for post-1960 singles. A future deduction does not reduce the down payment or the monthly payment.
• Match the names. The FAA registered owner, the borrower on the note and the named insured on the policy should be the same party. A mismatch found at closing causes delays.
• Entity borrowers bring more paperwork. Expect formation documents, a resolution authorizing the loan, business tax returns or financial statements, and a personal guarantee. See co-signers and guarantors.
• Decide before the purchase agreement. Moving the aircraft from you to an entity after closing usually requires the lender's consent and can trigger sales or use tax. See aircraft sales tax by state.

How this guide differs from related guides

This page owns the qualifying-use test and the ownership decision. Recovery periods, bonus depreciation math and recapture are in aircraft depreciation after the 2025 tax law. First-year timing, deductible operating expenses and how financing interacts with bonus depreciation are in the year-of-purchase aircraft tax deduction playbook. Choosing a professional is covered in how to hire an aviation tax advisor.

Frequently asked questions

General information as of September 2026, not tax or legal advice. Examples are illustrative. Confirm with a CPA or aviation tax attorney for your situation.