Yes, you can write off a trailer you use for your business, and in most cases you can deduct the entire purchase price in the year you put it to work. Two provisions do the heavy lifting: Section 179 expensing and 100% bonus depreciation. Both let you take the full cost up front instead of spreading it across several years. The size of the deduction tracks how much you actually use the trailer for business, and letting business use slip below 50% can force you to pay back deductions you already claimed.
The 50% Business Use Rule
Before any of the deduction mechanics matter, the trailer has to be an “ordinary and necessary” business expense. Ordinary means common and accepted in your line of work; necessary means helpful and appropriate for what you do.1Office of the Law Revision Counsel. 26 U.S.C. 162 – Trade or Business Expenses A flatbed makes sense for a construction company. A boat trailer probably doesn’t for an accounting firm.
If you use the trailer for both work and personal purposes, only the business portion is deductible. A trailer used 80% for hauling equipment to job sites and 20% for weekend trips gives you an 80% deduction on the purchase price and all related expenses.2Internal Revenue Service. Publication 334, Tax Guide for Small Business The IRS wants that split documented, not estimated at tax time.
A trailer used for transporting goods or equipment generally counts as “listed property” under the tax code.3Office of the Law Revision Counsel. 26 U.S.C. 280F – Limitation on Depreciation for Luxury Automobiles and Listed Property That designation carries a hard threshold. Business use must exceed 50% in the year you place the trailer in service to qualify for Section 179 or bonus depreciation. At or below 50%, you’re limited to slower straight-line depreciation. If business use later falls under 50%, the IRS requires recapture: you pay back the difference between the accelerated deduction you took and what straight-line would have produced over the same period.
Taking the Full Cost in the First Year
Most small businesses buying a trailer can deduct the entire cost in year one using Section 179, 100% bonus depreciation, or both together. These aren’t loopholes. They’re provisions written specifically to encourage equipment purchases.
Section 179 Expensing
Section 179 lets you deduct the full purchase price of qualifying business property in the year you place it in service. For the 2026 tax year, the maximum Section 179 deduction is $2,560,000, and it phases out dollar-for-dollar once total qualifying equipment purchases exceed $4,090,000.4Internal Revenue Service. Instructions for Form 4562, Depreciation and Amortization A single trailer isn’t going to brush those ceilings.
Section 179 has one real limitation: the deduction can’t exceed your total taxable business income for the year.4Internal Revenue Service. Instructions for Form 4562, Depreciation and Amortization If your business nets $30,000 and you buy a $40,000 trailer, you can only deduct $30,000 this year. The remaining $10,000 carries forward to future years.5eCFR. 26 CFR 1.179-2 – Limitations on Amount Subject to Section 179 Election You claim the deduction on Form 4562.6Internal Revenue Service. About Form 4562, Depreciation and Amortization
100% Bonus Depreciation
Bonus depreciation is a separate provision that also allows a 100% first-year deduction. Under the One, Big, Beautiful Bill, 100% bonus depreciation was made permanent for property acquired after January 19, 2025.7Internal Revenue Service. Treasury, IRS Issue Guidance on the Additional First Year Depreciation Deduction Amended as Part of the One, Big, Beautiful Bill Trailers qualify easily; the provision covers tangible property with a MACRS recovery period of 20 years or less.8Office of the Law Revision Counsel. 26 U.S.C. 168 – Accelerated Cost Recovery System
Bonus depreciation has two advantages Section 179 doesn’t. It has no business income limit, so it can create or deepen a net operating loss. And it works for both new and used trailers, as long as the trailer is new to you. The tradeoff: bonus depreciation is mandatory unless you elect out of it for an entire class of property. You can’t pick and choose asset by asset within a class.
Combining the Two
The usual play is to apply Section 179 up to your business income limit, then let bonus depreciation absorb whatever’s left. Say your business earns $25,000 in taxable income and you buy a $35,000 enclosed trailer. You claim $25,000 under Section 179, then take 100% bonus depreciation on the remaining $10,000. The trailer is fully written off, and the bonus portion generates a net operating loss you can carry forward. This only works if business use exceeds 50%.2Internal Revenue Service. Publication 334, Tax Guide for Small Business
Small Utility Trailers: The De Minimis Safe Harbor
If you’re buying a basic utility trailer for a few thousand dollars, there’s a simpler path. The de minimis safe harbor lets you expense items costing $2,500 or less per invoice without Section 179, bonus depreciation, or any depreciation schedule at all. Businesses with audited financial statements can use a $5,000 threshold.9Internal Revenue Service. Tangible Property Final Regulations
You make the election annually on your tax return, and it applies to the invoice cost. For an $1,800 open trailer, expense it, deduct it, and skip Form 4562 entirely.
What Counts Toward the Trailer’s Cost
The amount you write off isn’t just the sticker price. Your cost basis includes sales tax, freight charges, and any installation or setup costs.10Internal Revenue Service. Publication 551, Basis of Assets If you paid $800 in sales tax and $400 for delivery on a $15,000 trailer, your depreciable basis is $16,200. Those added amounts aren’t separately deductible; they’re rolled into the asset’s cost and recovered through whichever depreciation method you choose.
Routine maintenance and minor repairs don’t go into basis. Those are current-year expenses, deducted separately.
Ongoing Trailer Expenses
The purchase deduction is only the beginning. The day-to-day costs of owning the trailer are separately deductible as ordinary business expenses, prorated by your business use percentage.
- The business-use portion of your insurance premium and annual registration fees is deductible.11Internal Revenue Service. Topic No. 510, Business Use of Car
- If you financed the trailer, loan interest is deductible as a business expense. Unlike personal vehicle loan interest, business equipment loan interest has no annual dollar cap.12Office of the Law Revision Counsel. 26 U.S.C. 163 – Interest
- Routine maintenance such as tires, bearings, and brake work is deductible as a repair in the year you pay for it.
Repairs vs. Improvements
Not every dollar you spend on an existing trailer is a current-year write-off. The IRS separates repairs (deductible now) from improvements (capitalized and depreciated). You have to capitalize spending that makes the trailer better than it was, restores it from a non-functional state, or adapts it to a different use.9Internal Revenue Service. Tangible Property Final Regulations
Replacing worn brake pads is a repair. Adding a refrigeration unit to a flatbed is an improvement, and gets capitalized. Replacing an entire axle assembly can go either way depending on whether it’s a major component. A safe harbor covers routine maintenance you expect to perform more than once during the trailer’s class life to keep it in ordinary operating condition; that work is deductible as a repair.9Internal Revenue Service. Tangible Property Final Regulations
What Happens When You Sell
Selling a trailer you’ve already written off creates a tax bill many owners don’t see coming. A trailer is Section 1245 property, so any gain on the sale is taxed as ordinary income up to the total depreciation you claimed.13Internal Revenue Service. Publication 544, Sales and Other Dispositions of Assets
The math: say you bought a trailer for $20,000 and took a full $20,000 Section 179 deduction. Your adjusted basis is zero. If you sell three years later for $8,000, the entire $8,000 is ordinary income, not a capital gain. You don’t get the lower capital gains rate because the gain is attributable to depreciation you already deducted.
The recapture amount is the lesser of total depreciation claimed or gain on the sale. Only gain above the total depreciation claimed can be treated as a Section 1231 gain and potentially qualify for capital gains rates.13Internal Revenue Service. Publication 544, Sales and Other Dispositions of Assets On a trailer you’ve fully written off, it’s almost impossible for the sale price to top the original purchase price, so practically all of the gain comes back as ordinary income. The deduction isn’t free money. It’s a deferral that moves income from the purchase year to the sale year.
Records You Need to Keep
Listed property documentation is stricter than for ordinary business expenses, and transportation trailers sit in that category. You need two kinds of records: proof of purchase and proof of ongoing business use.
For the purchase, keep the invoice, proof of payment, and any registration documents showing when the trailer was placed in service. That date fixes which tax year the deduction belongs to, and the IRS will check if your return is examined.
For business use, the IRS expects contemporaneous records: logs created at or near the time of each use, showing the date, destination, business purpose, and duration. Reconstructing a log from memory at year-end is the kind of evidence that falls apart under audit. If the trailer stays at a job site and never leaves business use, that’s easier to document, but you still need records establishing the pattern.
Keep everything tied to the trailer, including depreciation schedules and improvement receipts, until the statute of limitations closes on the year you sell or dispose of it.14Internal Revenue Service. How Long Should I Keep Records? That’s typically three years after you file the return for the disposal year, but can stretch to six or seven if the IRS suspects underreported income. Holding records for the entire time you own the trailer plus six years after selling is the safe practice.