Disclaimer. This page is general education, not tax advice. Section 179 limits and rules change. Confirm current-year figures and your eligibility with your tax professional before acting.
What expensing means
Standard tax treatment spreads an equipment deduction across a depreciation schedule — a slice each year for several years. Section 179 is an election to take the deduction up front: qualifying cost comes off taxable business income in the year the equipment is placed in service.
The election does not create free money. It moves tax relief forward in time. For a profitable business buying equipment it planned to buy anyway, that timing shift can meaningfully change the first-year cost of owning the machine.
The mechanics in one sentence: a business that places a $150,000 qualifying machine in service and elects to expense it reduces that year's taxable business income by $150,000, instead of by a fraction of that amount each year for several years. What the deduction is worth in cash depends entirely on the business's tax situation. Illustrative example — not an offer, a quote, or tax advice.
What qualifies
In general terms: tangible business equipment — machinery, certain vehicles, computers, certain software, some building improvements — purchased and placed in service during the tax year, and used more than half the time for business. Both new and used equipment can qualify, provided the equipment is new to you.
Placed in service is the operative phrase. The clock runs on when the equipment is ready and available for use in the business, not on when it was ordered or paid for.
Business use is measured, not assumed. Equipment used partly for business generally supports a deduction proportional to that business use, and if business use later drops below the qualifying threshold, part of an earlier deduction can be recaptured as income. Mixed-use assets — vehicles especially — deserve a specific conversation with your tax professional.
Watch for
The deduction follows the placed-in-service date. Equipment ordered — even paid for — in December but not delivered and working until January belongs to the later tax year.
Financed equipment can qualify
Financing does not disqualify the deduction. Eligibility turns on ownership for tax purposes and the placed-in-service date, not on whether the invoice was paid in cash. A business can finance most or all of a purchase and still elect to expense the qualifying cost in year one, subject to the limits.
Structure matters, though. Loans and lease structures that transfer ownership — a $1 buyout lease, for example — are generally treated as purchases. A fair-market-value lease generally is not, because the lessor owns the equipment; the lessee typically deducts lease payments instead. Which side of that line your contract falls on is a question for your tax professional, with the contract in hand.
The combination most buyers are asking about: payments spread over the term while the deduction lands in year one. That mismatch is real and it is legal. It is also exactly the kind of planning decision to run past the person who prepares your return.
Limits exist and change
Section 179 carries an annual dollar cap on the total deduction and a phase-out threshold: once a business places more than a set amount of equipment in service in a single year, the available deduction shrinks dollar for dollar. Both figures are adjusted over time and have moved repeatedly.
This page deliberately does not print the current numbers. Any figure published here would eventually be wrong, and equipment decisions get made on stale numbers more often than you would think. Confirm current limits with your tax professional or against the IRS's published figures for the tax year in question.
Bonus depreciation is the companion provision: a separate percentage-based first-year deduction with its own statutory schedule, applied after Section 179. Its percentage has changed several times in recent years. Same instruction — confirm the current figure before you build a plan on it.
State treatment is its own question. Not every state conforms to the federal rules; some set their own limits, and some do not allow the election at all. A deduction that works on the federal return can look different on the state one — a further reason the current-year check belongs with your tax professional, not with a web page.
The business income limitation
Section 179 cannot take taxable business income below zero. The election is capped at your income from active trades or businesses for the year; the excess carries forward to future years rather than vanishing.
This is where planning earns its keep. A business expecting a thin year may see little immediate value from the election, and the interplay with bonus depreciation — which follows different rules — is return-specific. Bring your tax professional the equipment quote and the financing terms before year end, not after.