Tax deductions reduce your taxable income — meaning you pay taxes on a smaller number, which directly reduces your tax bill. The frustrating reality is that the US tax code is full of legal deductions that millions of taxpayers miss every year, either because they don’t know about them or because they assume the deductions are too complicated to claim.
This guide covers the most commonly missed deductions for employees, freelancers, and small business owners.
How Tax Deductions Work
A deduction reduces your taxable income by the deduction amount. If you’re in the 22% tax bracket and claim a $1,000 deduction, you save $220 in taxes. It’s not a dollar-for-dollar reduction in your tax bill — it’s a reduction in the income on which you’re taxed.
The IRS gives you two options: take the standard deduction (a flat amount that anyone can claim without itemizing) or itemize your deductions (list out eligible expenses if they total more than the standard deduction).
For 2026, the standard deduction is approximately $15,000 for single filers and $30,000 for married filing jointly. Most people take the standard deduction — but those with significant mortgage interest, state/local taxes, or charitable giving may benefit from itemizing.
Commonly Missed Deductions for Employees
Student Loan Interest
You can deduct up to $2,500 in student loan interest paid per year — even if you take the standard deduction. This is an “above-the-line” deduction, meaning you don’t have to itemize to claim it. Income limits apply.
Educator Expenses
K-12 teachers and educators can deduct up to $300 ($600 for married educators filing jointly) for classroom expenses paid out of pocket — supplies, books, software. Also an above-the-line deduction.
Health Savings Account (HSA) Contributions
Contributions to an HSA are fully deductible, even without itemizing. If you made out-of-pocket HSA contributions (beyond payroll deductions), make sure they’re recorded on your return.
Traditional IRA Contributions
If you made deductible Traditional IRA contributions, these reduce your taxable income. Easy to miss if your tax software doesn’t prompt you clearly.
Alimony Paid (Pre-2019 Divorces)
For divorce agreements finalized before 2019, alimony payments are still deductible for the payer.
Deductions for Freelancers and Side Hustlers
Self-employment opens up a significant range of deductible business expenses. If you have any self-employment income — side hustle, freelance, consulting — these deductions can substantially reduce your tax liability.
Home Office Deduction
If you use part of your home regularly and exclusively for business, you can deduct a portion of your rent or mortgage, utilities, and internet. Two methods: the simplified method ($5 per square foot, up to 300 sq ft) or the regular method (percentage of home used for business × actual home expenses). Regular method is more work but often yields a larger deduction.
Business Use of Your Car
If you use your car for business travel (not commuting), you can deduct either actual expenses (gas, insurance, maintenance — allocated to business use) or the standard mileage rate (67 cents per mile in 2024; check current rates). Keep a mileage log.
Business Equipment and Software
Computer, phone (business use portion), software subscriptions, professional tools and equipment — all deductible as business expenses. Section 179 of the tax code allows you to deduct the full cost of qualifying equipment in the year of purchase rather than depreciating it.
Professional Development
Courses, certifications, books, and conferences related to your current work are deductible as business expenses.
Health Insurance Premiums
If you’re self-employed and pay your own health insurance (not through a spouse’s employer plan), premiums are 100% deductible as an above-the-line deduction.
Self-Employment Tax Deduction
You can deduct half of the self-employment tax you pay (the employer portion). This is calculated on Schedule SE and automatically flows to your Form 1040.
Commonly Missed Itemized Deductions
Charitable Contributions
Cash donations to qualified charities are deductible (with documentation). Non-cash donations (clothing, furniture, appliances) are also deductible at fair market value. Volunteer mileage (14 cents/mile) is deductible. Keep all receipts and written acknowledgments for donations over $250.
Mortgage Interest and Property Taxes
Interest on mortgage debt up to $750,000 is deductible. State and local property taxes are deductible up to the $10,000 SALT cap combined with state income taxes.
Medical Expenses
Out-of-pocket medical expenses exceeding 7.5% of your adjusted gross income are deductible. This threshold means it’s only relevant for people with very high medical costs, but worth tracking if you had a significant medical year.
Working with a Tax Professional
If you have self-employment income, significant investments, rental property, or a complex financial situation, a CPA or enrolled agent can often save you far more than their fee. A competent tax professional knows the deductions applicable to your situation — and knows how to document them correctly to withstand an audit.
Free resources: The IRS Free File program provides free tax software for those under income limits. VITA (Volunteer Income Tax Assistance) offers free tax preparation for qualifying individuals.
