Small Business Tax Deductions Most People Miss

Home Office Deduction: The Rule and How to Qualify

If you use part of your home regularly and exclusively for business, you can deduct home office expenses. Exclusive use means that corner of the living room does not double as the family TV spot. Regular use means you work there consistently, not once a month.

Two calculation methods: simplified ($5 per square foot, up to 300 sq ft, max $1,500 deduction) or actual expenses (pro-rate mortgage interest, rent, utilities, insurance, repairs based on the square footage percentage of your home). Choose whichever gives the larger deduction each year.

The simplified method requires minimal records and no depreciation recapture when you sell your home. The actual expense method requires keeping receipts for all home expenses but often produces a larger deduction for dedicated home offices. You can switch methods year to year.

Even if you do not qualify for the home office deduction because you use the space for both work and personal life, you can still deduct business furniture, equipment, supplies, and a dedicated business internet line if you have one.

Vehicle and Mileage Deductions

For 2026, the standard mileage rate is 70 cents per business mile. That covers gas, maintenance, insurance, registration, and depreciation. If you drive 250 business miles per week, that is roughly a $9,000 annual deduction.

You must log each trip: date, miles driven, business purpose, and starting/ending locations. A contemporaneous log (recorded at the time) is far more defensible than a reconstructed log. Mobile apps like MileIQ, TripLog, or a simple notebook all work.

Commuting from home to your primary workplace is not deductible. But driving from your home office to a client site, between job sites, or to pick up supplies is deductible. For sole proprietors with a qualified home office, the home office becomes the starting point and trips from there are business miles.

Actual expense method: instead of the standard mileage rate, you can deduct the business percentage of all vehicle costs—gas, oil, tires, repairs, insurance, registration, lease payments, and depreciation. This usually works better for expensive vehicles with high operating costs. Once you use actual expenses the first year, you are locked into it for that vehicle.

Equipment, Software, and Section 179

Section 179 lets you deduct the full cost of qualifying equipment and software in the year you buy and place it in service, up to a statutory limit (estimated $1,250,000+ for 2026). This includes computers, office furniture, machinery, tools, and certain vehicles over 6,000 lbs GVWR.

Bonus depreciation allows 60% first-year write-off (phased down from 100% in 2022, decreasing 20% per year through 2027) for new and used property with a recovery period of 20 years or less. It applies automatically unless you elect out.

Software subscriptions (QuickBooks, Adobe, Slack, cloud storage, design tools, email marketing, CRM) are fully deductible as ordinary business expenses. Do not capitalize them—deduct them in the year paid.

The de minimis safe harbor lets you deduct tangible property costing $2,500 or less per item or invoice without capitalizing and depreciating. This covers most small tools, minor equipment, tablets, and peripherals. You need a written accounting policy in place at the beginning of the year.

Health Insurance, Retirement, and Self-Employment Tax Reductions

Self-employed health insurance premiums for you, your spouse, and dependents are an above-the-line deduction (Schedule 1, line 17) that reduces adjusted gross income directly, not as an itemized deduction. This includes medical, dental, vision, and qualified long-term care premiums. You do not need to itemize to claim it.

SEP IRA contribution limit for 2026: 25% of net self-employment earnings, up to a maximum of approximately $70,000. A Solo 401k allows employee deferrals ($23,000 for 2026, plus $7,500 catch-up if 50+) plus employer contributions up to 25% of compensation, for a potential combined contribution of $70,000+.

You can deduct half of your self-employment tax (the employer-equivalent portion) on Form 1040 Schedule 1, line 15. This is an adjustment to income, not an itemized deduction. While it does not reduce your self-employment tax itself, it reduces your income tax.

Qualified Business Income (QBI) deduction: up to 20% of qualified business income for pass-through entities. Available through 2025 under the Tax Cuts and Jobs Act. It may be extended but plan conservatively. It phases out for higher-income service businesses.

Health Savings Account (HSA) contributions are deductible above the line if you have a qualifying high-deductible health plan. For 2026: $4,300 individual, $8,550 family, plus $1,000 catch-up at 55+. The money goes in pre-tax, grows tax-free, and comes out tax-free for medical expenses.

Startup Costs, Education, and Miscellaneous

Up to $5,000 of startup costs can be deducted in the first year of business, reduced dollar-for-dollar if total startup costs exceed $50,000. Remaining costs are amortized over 180 months. Startup costs include market research, advertising before opening, employee training, and professional fees for setting up the entity.

Business loan interest, credit card interest (if the card is used exclusively for business), and bank account fees are fully deductible. Merchant processing fees (credit card processing charges) are also fully deductible as a business expense.

Continuing education, industry conferences, certifications, books, and trade publications are deductible if they maintain or improve skills in your current business. Education that qualifies you for a new trade or business is not deductible.

Bad debts from unpaid invoices: if you use accrual accounting, you can deduct specific bad debts in the year they become worthless. Cash-basis taxpayers do not report income until received and therefore do not get bad debt deductions (you never reported the income in the first place).

Business gifts are deductible up to $25 per recipient per year. Promotional items under $4 with your business name permanently printed do not count toward the $25 limit. Meals are 50% deductible in most cases; meals provided at office events for all employees are 100% deductible.