Deductible Expenses for Contractors

A Practical Guide to Protecting Your Profit Margin, Strengthening Your Records, and Preparing for Tax Season

For a contractor, identifying a deduction is only half the job. The other half is being able to show that the expense was legitimate, related to the business, and supported by sufficient documentation. Organized bookkeeping can do more than reduce your tax burden: it can also help you understand the true margin on each project, make better purchasing decisions, and respond more confidently to a tax review.

The Rule That Governs Deductions

In general terms, a business expense must be ordinary and necessary. “Ordinary” means that it is common and accepted in your trade or business. “Necessary” means that it is helpful and appropriate for operating the business. The final deductibility of an expense depends on the facts, its business use, and the documentation available.

Expenses That Are Often Relevant in Construction

These categories deserve a systematic review throughout the year:

• Materials and supplies purchased for customer projects.

• Hand tools, consumables, and small equipment used on the job.

• Commercial insurance, including liability coverage and, when applicable, workers’ compensation.

• Licenses, permits, professional dues, and regulatory costs related to the business.

• Protective equipment and specialized clothing that is not suitable for everyday use.

• Professional fees, advertising, administrative services, and business banking costs.

• Payments to subcontractors, provided that the classification and documentation are correct.

• The business portion of telephone, internet, and home office expenses, when applicable requirements are met.

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The key checkpoint: Paying for something from a business account does not automatically make it deductible. There must be a clear connection to the business, along with documentation showing what was purchased, when it was purchased, how much it cost, and which project or business purpose it supported.

Vehicles and Mileage

For 2026, the IRS optional standard mileage rate for business use is 72.5 cents per mile. You may also consider the actual expense method, which includes costs such as fuel, repairs, insurance, registration, and depreciation, applied according to the percentage of business use. The two methods cannot be freely combined for the same vehicle, and rules apply regarding when each method must be selected.

Be careful with personal commuting. Regular travel between your home and your usual place of work is generally considered personal commuting. However, certain trips between work locations or to temporary work sites may receive different treatment. A contemporaneous record showing the date, destination, purpose, and mileage of each trip is essential.

Tools, Machinery, and Vehicles

Higher-value purchases are not always treated the same way as ordinary supplies. Depending on the asset and the circumstances, the cost may be recovered through regular depreciation, a Section 179 election, bonus depreciation, or another applicable rule. The fastest deduction does not always produce the best result. You should consider the business’s profit for the year, business use, vehicle limitations, and future tax projections.

Before committing to a major purchase, consider modeling the tax impact. A capital investment should make sense for the business first and provide a tax benefit second.

Subcontractors and Form 1099

For tax years beginning after 2025, the general threshold for certain reportable payments increases to $2,000. However, the threshold alone does not determine whether a reporting requirement exists. The type of payment, the provider’s legal structure, the payment method, and possible exceptions may change the analysis. Request Form W-9 before making the first payment and retain contracts, invoices, payment records, and evidence supporting the worker’s classification.

Classification matters. Calling someone a “subcontractor” does not determine their tax status. If the relationship resembles that of an employee, payroll, withholding, insurance, and penalty obligations may arise.

Five Mistakes That Can Weaken a Deduction

Mistake	Risk and Best Practice
Mixing funds	Makes it difficult to separate personal and business expenses. Use dedicated accounts and perform regular reconciliations.
Keeping only the bank or credit card statement	The charge shows that a payment was made, but it may not show what was purchased or its business purpose. Keep receipts and invoices.
Reconstructing mileage at the end of the year	Late estimates are less reliable. Maintain a contemporaneous record of every business trip.
Paying without a W-9	May prevent accurate reporting and complicate the deduction. Obtain the form before making payment.
Buying something only for the deduction	A deduction reduces taxable income; it does not turn an unnecessary expense into a good investment.

A Simple System That Works

The best strategy does not begin in April. It is built throughout the year with a brief and consistent routine:

• Use separate accounts and credit cards for business activity.

• Capture every receipt and add the business purpose while you still remember it.

• Record mileage contemporaneously.

• Review transactions monthly and correct questionable classifications.

• Evaluate profitability, estimated tax payments, and capital purchases quarterly.

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The result goes beyond the tax return. Reliable records allow you to bid on jobs using better information, identify margin leaks, manage cash flow, and present a stronger financial picture to banks, insurers, and business partners.

When It Makes Sense to Speak with a CPA

Seek professional guidance before purchasing a major vehicle or piece of equipment, changing your legal structure, hiring employees, expanding operations into another jurisdiction, or making significant payments to subcontractors. At those moments, an early review is often more valuable than correcting the treatment months later.

Lifaver Trujillo, CPA, PLLC

We help business owners in North Carolina maintain reliable records, meet their compliance obligations, and make decisions using better financial information. Our services include bookkeeping, payroll, tax compliance, tax planning, and financial consulting.

Talk with us about your business needs.

(919) 590-3610 | 4804 Page Creek Lane, Suite 114, Durham, NC 27703 | www.ltrujillocpa.com

Official Sources

IRS Publication 535: Business Expenses | IRS Publication 463: Travel, Gift, and Car Expenses | 2026 Standard Mileage Rates

Disclaimer: This content is for informational purposes only and does not constitute tax, legal, or financial advice. The application of these rules depends on the facts and circumstances of each taxpayer. Consult with a professional before making decisions.