Bonus Depreciation vs Section 179: Two Different Tools

September 10, 2026 · 7 min read · Equipment Funding Network

If you are financing equipment, someone will eventually tell you it is a tax write-off. That is broadly true and unhelpfully vague. There are two separate mechanisms most often involved — the Section 179 election and bonus depreciation — and they behave differently in ways that matter. This is an explanation of the shape of each, not tax advice; the numbers have to be run by your own CPA against your own return.

The basic difference

Section 179 is an election you make, asset by asset, to expense qualifying property in the year it is placed in service rather than depreciating it over its useful life. Because it is an election, you control how much you take, which makes it a precision tool.

Bonus depreciation applies to qualifying property more automatically and is generally taken across whole classes of assets rather than selected item by item. It is the blunter instrument of the two, and you elect out of it rather than into it.

Three differences worth knowing about

• Income limitation — the Section 179 deduction is generally limited by business income and cannot be used to create a loss. Bonus depreciation is not constrained the same way, which matters if you are already near break-even.
• Caps and phase-outs — Section 179 has annual dollar limits and a phase-out once total qualifying purchases exceed a threshold. Bonus depreciation works differently and the applicable percentage has changed over recent years.
• State conformity — states do not all follow the federal rules. A deduction that works federally may be reduced or disallowed on your state return, and this catches people out regularly.

Why financing does not change eligibility

A common and reasonable question is whether financed equipment qualifies, given you have not paid cash for it. Generally the relevant test is that the asset is acquired and placed in service, not that it is paid off — which is why a business can finance a machine and still take an accelerated deduction in that year. The mechanics of your particular structure matter, though, and a true lease is not treated the same way as a purchase.

That distinction is one of the most important reasons to know whether your agreement is a loan, a capital lease or an operating lease before you sign it. The tax treatment follows the structure.

Placed in service is the deadline, not delivery

Deductions generally attach to the year the equipment is placed in service — available and ready for its intended use — rather than the year it was ordered or paid for. A machine delivered in late December but not operational until January can fall into the following tax year.

This is why year-end equipment purchases get busy, and why it is worth confirming realistic delivery and commissioning dates rather than assuming a December invoice settles the question.

The argument against maximising the deduction

Writing an asset off entirely in year one removes the depreciation you would otherwise have claimed in later years. If you expect materially higher income in future, spreading the deduction can be worth more overall. A large deduction taken in a low-income year can be the least valuable version of it.

There is also a plain business point underneath the tax one: a deduction reduces tax on money you spent, it does not refund the money. Equipment you did not need is not made worthwhile by its tax treatment.

Common follow-up questions

Can I take Section 179 on financed equipment?
Generally the test is whether the asset was acquired and placed in service, not whether it is paid off, so financed purchases commonly qualify. Your structure matters — a true lease is treated differently from a purchase — so confirm with your CPA.

Which is better, Section 179 or bonus depreciation?
Neither is universally better, and many businesses use both in the same year. The right combination depends on your income, your total purchases, your state's rules and what you expect next year — which is precisely why this is a CPA question.

What does 'placed in service' actually mean?
Broadly, that the equipment is available and ready for its intended use. Delivery alone may not be enough if the machine still needs installation or commissioning before it can operate.

Do states follow the federal rules?
Not uniformly. Several states limit or decouple from these provisions, so the federal and state answers can differ. Ask your accountant about your specific state before relying on a deduction.