What is the most overlooked small business tax deduction?

Retirement plan contributions are consistently the most underutilized deduction. A sole proprietor or S-Corp owner contributing to a SEP-IRA or Solo 401(k) can deduct up to $70,000 per year (2026 limit), significantly reducing taxable income while building retirement wealth. Many small business owners either don't know about this or don't set up the plan before the deadline.

Can I deduct meals and entertainment as a business expense?

Meals with a legitimate business purpose (meeting with a client, prospective customer, or business associate) are 50% deductible. Entertainment expenses — sporting events, concerts, golf outings — are generally not deductible under current law (eliminated by the Tax Cuts and Jobs Act). Meals at entertainment events may be deductible at 50% if separately documented. Keep detailed records noting the business purpose and attendees.

What documentation do I need to support business deductions?

For most deductions, you need a receipt or bank/credit card statement showing the amount and payee, plus a record of the business purpose. For vehicle deductions, you need a mileage log with date, destination, miles, and business purpose for each trip. For home office, you need square footage measurements. For meals, note the attendees and business purpose at the time — trying to reconstruct this later is a red flag in an audit.

Tax Deductions for Small Business Owners: The Complete List

May 25, 2026

How Business Deductions Work

Business deductions reduce your taxable income dollar-for-dollar. A $10,000 deduction at a 25% combined marginal tax rate saves $2,500 in taxes. The goal is not to spend money to save on taxes — that is backwards thinking — but to ensure every legitimate business expense is identified and documented properly so you do not overpay.

Operating Expenses

Rent and lease payments: Office space, co-working memberships, equipment leases — fully deductible
Utilities: Electric, internet, phone — for business-use portions
Office supplies: Stationery, printer ink, folders, postage
Software subscriptions: Accounting software, project management tools, CRM systems, design tools
Professional services: CPA fees, legal fees, consulting fees, bookkeeping services
Insurance: Business liability, professional liability, property insurance, business interruption
Advertising and marketing: Website costs, Google Ads, social media advertising, print materials

Employee and Contractor Costs

Salaries and wages: Fully deductible, including your employees' pay (not your own W-2 salary if you are an S-Corp — that is already excluded from net profit)
Payroll taxes: Employer's share of Social Security, Medicare, FUTA, SUTA
Employee benefits: Health insurance premiums, retirement plan employer contributions, paid leave
Contractor payments: 1099 payments to independent contractors — fully deductible but require Form 1099-NEC if you pay $600+ in a year

Vehicle and Travel

Standard mileage rate: 70 cents per mile driven for business in 2026 (IRS rate announced annually)
Actual vehicle expenses: Gas, insurance, repairs, depreciation — deductible in proportion to business use percentage
Business travel: Airfare, hotels, Uber/Lyft, baggage fees — fully deductible for legitimate business trips
Meals while traveling: 50% deductible for meals while traveling overnight for business

Equipment and Depreciation

Section 179 expensing: Deduct up to $1,220,000 of qualifying equipment in the year purchased (2026 limit), rather than depreciating over several years
Bonus depreciation: 40% of qualifying assets placed in service can be expensed immediately in 2026 (phasing down from 100% over several years)
Regular depreciation: For assets not expensed under Section 179 or bonus depreciation, use the MACRS schedule appropriate to the asset class

Home Office Deduction

If you use a space in your home regularly and exclusively for business, you can deduct it. The simplified method: $5 per square foot, up to 300 sq ft ($1,500 max). The regular method: actual expenses × (office sq ft ÷ total home sq ft). The regular method almost always produces a larger deduction for homeowners.

Retirement Plan Contributions

SEP-IRA: Up to 25% of net self-employment income or $70,000 in 2026 — contributions due by tax filing deadline including extensions
Solo 401(k): Employee contributions up to $23,500 (plus $7,500 catch-up if 50+) plus employer profit-sharing up to 25% of W-2 wages — plan must be established by December 31
SIMPLE IRA: For businesses with up to 100 employees — employee contributions up to $16,500 plus employer match

Other Commonly Missed Deductions

Bank fees and merchant processing fees
Business loan interest
Education and professional development (directly related to your current business)
Trade association dues and professional memberships
Business-related subscriptions and publications
Startup costs (up to $5,000 deductible in year one for new businesses)

Work with a CPA who specializes in small business taxes to ensure you capture every deduction. Browse CPAs by city to find a specialist near you.

Frequently Asked Questions

What is the most overlooked small business tax deduction?: Retirement plan contributions are consistently the most underutilized deduction. A sole proprietor or S-Corp owner contributing to a SEP-IRA or Solo 401(k) can deduct up to $70,000 per year (2026 limit), significantly reducing taxable income while building retirement wealth. Many small business owners either don't know about this or don't set up the plan before the deadline.
Can I deduct meals and entertainment as a business expense?: Meals with a legitimate business purpose (meeting with a client, prospective customer, or business associate) are 50% deductible. Entertainment expenses — sporting events, concerts, golf outings — are generally not deductible under current law (eliminated by the Tax Cuts and Jobs Act). Meals at entertainment events may be deductible at 50% if separately documented. Keep detailed records noting the business purpose and attendees.
What documentation do I need to support business deductions?: For most deductions, you need a receipt or bank/credit card statement showing the amount and payee, plus a record of the business purpose. For vehicle deductions, you need a mileage log with date, destination, miles, and business purpose for each trip. For home office, you need square footage measurements. For meals, note the attendees and business purpose at the time — trying to reconstruct this later is a red flag in an audit.