For Arizona business owners, the last eight weeks of the year bring the usual pressures: holiday staffing in Scottsdale retail, peak season for Phoenix landscapers and HVAC contractors, and year-end inventory. They also bring one of the most valuable tax opportunities in the federal code, and many owners still leave it on the table.
Section 179 lets a business deduct the full cost of qualifying equipment in the year it’s placed in service, instead of depreciating it over five, seven, or more years. Combined with bonus depreciation, which federal legislation in 2025 restored at 100% for qualifying property, 2026 is one of the most generous years for capital investment in recent memory.
Here’s what Arizona owners need to know before December 31.
What Section 179 Actually Does
Normally, when a business buys a $150,000 excavator, it can’t deduct $150,000 that year. The IRS requires the cost to be spread across the asset’s useful life under MACRS, the Modified Accelerated Cost Recovery System. For seven-year property, the first-year deduction is only about 14.29% of the cost.
Section 179 changes that. If you elect it, you can expense the entire qualifying cost in year one, subject to annual limits. Following the 2025 tax law changes, the deduction limit rose to $2.5 million, with a phase-out beginning at $4 million of qualifying purchases. Both figures are indexed for inflation, so confirm the exact 2026 numbers in IRS guidance, including Publication 946 at IRS.gov.
For most Arizona small and mid-sized businesses, those limits are effectively unlimited.
What Qualifies
Section 179 generally covers tangible business property, including:
- Machinery and equipment (construction, manufacturing, landscaping, medical)
- Computers, servers, and off-the-shelf software
- Office furniture and fixtures
- Business vehicles, with special limits for SUVs and passenger cars
- Certain improvements to nonresidential buildings, such as roofs, HVAC, fire protection, and security systems
The HVAC and roofing categories matter a great deal in Arizona’s climate. A Tempe office building owner replacing an aging rooftop cooling system may be able to expense the cost rather than depreciate it over 39 years.
The asset must be used more than 50% for business. It must also be placed in service, meaning delivered and ready for use, not just ordered, by December 31 to count for 2026.
A Phoenix Example: The Numbers in Practice
Consider a Phoenix plumbing and HVAC contractor organized as a C corporation. In November 2026, it buys $250,000 of equipment: two service vans outfitted with tools, diagnostic equipment, and a new dispatch software system.
| Scenario | First-year deduction | Federal tax savings (21%) |
| Standard 7-year MACRS | ~$35,725 | ~$7,500 |
| Section 179 election | $250,000 | ~$52,500 |
That’s roughly $45,000 in additional cash flow in year one. The deduction isn’t a free gift, since the asset will have no depreciation left in later years. But money saved today can be reinvested in hiring, inventory, or paying down a line of credit, and that time value is significant.
For a pass-through owner (an LLC, S corporation, or sole proprietorship) in a higher individual bracket, the savings can be larger. Owners can model their own scenario with the equipment financing calculator at USFinanceCalculators.com before meeting their CPA.
Section 179 vs. Bonus Depreciation: Which One to Use
These two provisions overlap, and choosing between them is a strategic decision.
Section 179
- Is elective, asset by asset, which gives you control
- Is limited to your business’s taxable income, so it can’t create a loss
- Is subject to the dollar cap and phase-out
Bonus depreciation
- Is applied automatically unless you elect out
- Can create or increase a net operating loss
- Has no dollar cap
A common approach is to use Section 179 for precise control up to taxable income, then let bonus depreciation cover any remainder. A business with a lean year might lean on bonus depreciation. A business wanting to smooth income across years might use Section 179 selectively and depreciate the rest normally.
The Arizona Angle: Don’t Assume State Conformity
This is where Arizona owners need to pay attention. Federal and state depreciation rules don’t always line up. Arizona has historically not fully followed federal bonus depreciation, requiring businesses to add back some or all of it and recover the cost over several years on the state return.
In practice, your federal deduction and your Arizona deduction for the same equipment may differ, creating a book-keeping difference you’ll track for years. With Arizona’s flat 2.5% individual income tax rate and 4.9% corporate rate, the dollars at stake on the state side are smaller than federal, but they’re not trivial. Check current conformity rules with the Arizona Department of Revenue at azdor.gov or with your tax advisor, because the legislature revisits conformity regularly.
Buy, Finance, or Lease? How Each Interacts with Section 179
How you acquire equipment changes how much of the deduction you can claim, and when.
Cash purchase. The simplest case. You own the asset, place it in service, and can elect Section 179 on the full cost. The trade-off is the cash leaving your operating account in the slowest season for many Arizona businesses, so check your working capital before committing.
Financed purchase. A bank loan or equipment financing still counts as a purchase. You can deduct the full cost in year one while paying for the asset over three to seven years. That combination of an upfront deduction and spread-out payments can produce positive cash flow in year one. For example, a $120,000 machine financed over five years at 8% carries payments of roughly $2,430 a month, while the deduction can save a 24% bracket owner about $28,800 in federal tax this year.
Capital lease (finance lease). If the lease is structured so you effectively own the asset at the end, such as with a $1 buyout, the IRS generally treats it as a purchase, and Section 179 can apply.
Operating lease (true lease). You don’t own the asset, so Section 179 doesn’t apply. Instead, you deduct lease payments as ordinary business expenses as you make them. That can still make sense for equipment that becomes obsolete quickly, such as technology.
Before signing any financing or lease documents, ask your lender how the agreement is classified and confirm the tax treatment with your CPA.
Five Year-End Mistakes to Avoid
- Ordering instead of placing in service. A truck that arrives on January 3 counts for 2027, not 2026. Supply chain delays still catch businesses off guard, so confirm delivery dates now.
- Buying equipment you don’t need. A tax deduction lowers the cost of a purchase. It doesn’t make an unnecessary purchase free. Spending $100,000 to save $21,000 in tax still leaves you $79,000 poorer if the asset doesn’t earn its keep.
- Ignoring the financing math. Section 179 applies to financed equipment too, so you can deduct the full cost even if you’ve only made a few payments. Compare the loan or lease cost against the tax benefit.
- Overlooking vehicle limits. Heavy SUVs and passenger cars face specific caps. Pickups and vans with qualifying configurations are often treated more favorably.
- Forgetting recapture. If business use drops to 50% or below, or you sell the asset early, part of the deduction may be recaptured as income.
The Bottom Line for Arizona Owners
With deduction limits now in the millions and full bonus depreciation back, 2026 is an unusually favorable year for Arizona businesses that already plan to invest in equipment, vehicles, or building systems. The deadline is real, though. The asset must be in service by December 31.
Run your numbers now, talk to your CPA about the federal–Arizona difference, and time your purchases accordingly. For free calculators covering depreciation, business loans, and tax planning, visit USFinanceCalculators.com.
About the author: David is the founder of USFinanceCalculators.com and holds an MBA in Finance. With nearly 20 years in finance and operations, he writes about business tax planning, valuation, and commercial lending.
This article is for educational purposes only and isn’t tax advice. Consult a qualified tax professional about your situation.
