Most small business owners overpay their taxes every year. Not because they are doing anything wrong, but because they simply do not know which deductions they are entitled to. The IRS does not send you a reminder about write-offs you missed. That is our job as your CPA.
Here are 10 commonly overlooked tax deductions every small business owner should know about heading into 2026.
1. Home Office Deduction
If you use a portion of your home exclusively and regularly for business, you may qualify for the home office deduction. This applies whether you rent or own. You can use the simplified method, which allows $5 per square foot up to 300 square feet, or the regular method based on the actual percentage of your home used for business. Many owners skip this because they are unsure if they qualify, but the bar is lower than most people think.
2. Vehicle Mileage
Every business-related drive is potentially deductible. Visiting a client, picking up supplies, attending a networking event, driving to the bank for business purposes, all of these count. The IRS standard mileage rate for 2026 should be confirmed at the start of the year, but typically runs around 67 cents per mile. The key is keeping a mileage log. Many business owners lose this deduction entirely because they cannot reconstruct their records at tax time.
3. Business Meals
Meals with clients, prospects, referral partners, or employees that have a clear business purpose are 50% deductible. The conversation must be business-related, not just friendly. Keep the receipt and jot down who was there and what business was discussed. A simple note in your phone right after the meal is enough.
4. Health Insurance Premiums
Self-employed business owners who pay for their own health insurance can deduct 100% of those premiums for themselves, their spouse, and their dependents directly from their income. This is not an itemized deduction, it comes right off your adjusted gross income. Many self-employed individuals miss this entirely because they assume it only applies to larger businesses.
5. Retirement Plan Contributions
Contributing to a SEP-IRA, SIMPLE IRA, or Solo 401(k) reduces your taxable income today while building your retirement security. A SEP-IRA allows contributions of up to 25% of net self-employment income. Contributions can typically be made as late as your tax filing deadline, including extensions, making this one of the most flexible last-minute deductions available.
6. Software and Subscriptions
Business-related software and subscription services are fully deductible as ordinary business expenses. This includes accounting software like QuickBooks, project management tools, cloud storage, email marketing platforms, scheduling apps, and industry-specific software. Review your monthly charges and confirm everything business-related is tracked.
7. Professional Development
Courses, books, webinars, industry publications, professional association dues, and conferences that maintain or improve skills required in your trade or business are deductible. If you took a continuing education course related to your profession, that qualifies. An unrelated personal interest class does not.
8. Bank Fees and Business Loan Interest
Monthly account maintenance fees, wire transfer fees, and the interest paid on business loans are all deductible business expenses. This is another area where having a dedicated business bank account and business credit card makes record-keeping straightforward and audit-proof.
9. Marketing and Advertising Expenses
Every dollar you spend promoting your business is deductible. This includes your website and hosting fees, social media advertising, Google Ads, business cards, brochures, signage, sponsored posts, and fees paid to a marketing agency or graphic designer. Do not overlook digital costs, these add up quickly and every dollar is a write-off.
10. Professional Services Fees
Fees paid to your CPA, business attorney, bookkeeper, financial consultant, or other professionals for business-related services are fully deductible. This means the cost of having your taxes prepared and the advice we give you throughout the year is itself a tax write-off.
How to Protect Your Deductions
The IRS requires substantiation for deductions, which means receipts, invoices, bank statements, and documentation of business purpose. The most common reason deductions get disallowed in an audit is poor recordkeeping, not ineligibility. Use a business credit card for all business purchases, keep digital copies of receipts, and document meals and mileage at the time they occur.
Working with a CPA year-round is the most reliable way to capture every deduction available to you and keep records in a form that holds up under IRS scrutiny.
Ready to put these strategies to work? Schedule a free consultation with Peters Bandura CPA at www.petersbandura.com or call our office. We work with small business owners year-round — not just at tax time.