What is the difference between above-the-line and below-the-line deductions?

Above-the-line deductions (like IRA contributions, student loan interest, and HSA contributions) reduce your Adjusted Gross Income (AGI) and can be claimed even if you take the standard deduction. Below-the-line deductions (like mortgage interest and charitable gifts) only benefit you if you itemize on Schedule A.

Should I itemize or take the standard deduction?

Itemize only if your total below-the-line deductions exceed the standard deduction ($15,400 single / $30,800 MFJ for 2026). Most filers benefit from the standard deduction. However, you should still claim all above-the-line deductions regardless.

What are the most commonly missed tax deductions?

Commonly missed deductions include student loan interest, HSA contributions, educator expenses, state and local sales tax (in lieu of income tax), charitable contributions of appreciated stock, home office deduction for self-employed, and self-employed health insurance premiums.

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25 Tax Deductions Every Filer Should Know About

Commonly missed tax deductions for employees, self-employed workers, investors, and families — from retirement contributions to charitable gifts.

Last updated on March 22, 2026

Tax deductions reduce your taxable income, which means less tax owed. Some deductions are available to everyone; others require itemizing or self-employment. Understanding the difference between deductions and tax credits is key — credits reduce your tax dollar-for-dollar, while deductions reduce the income that gets taxed. This guide covers 25 deductions worth checking before you file.

Key Takeaways

Above-the-line deductions reduce your AGI even if you take the standard deduction.
Itemized deductions only help if they exceed the standard deduction (estimated $15,400 / $30,800 for 2026).
Self-employed filers have access to the most deductions.
Timing deductions strategically (bunching) can save more than spreading them evenly.

Above-the-Line Deductions (Available to Everyone)

These deductions reduce your Adjusted Gross Income (AGI) regardless of whether you itemize. They are some of the most valuable because lowering AGI can also unlock other tax benefits (credits, phaseout thresholds, etc.).

1. Traditional IRA Contributions

Deduct up to $7,500 (2026, under 50) or $8,600 (50+) if you or your spouse are not covered by a workplace plan, or if your income is below the deduction phaseout. See our Traditional IRA guide.

2. HSA Contributions

Contributions to a Health Savings Account are fully deductible: $4,400 self-only or $8,750 family for 2026, plus $1,000 catch-up if 55+.

3. Student Loan Interest

Deduct up to $2,500 of student loan interest paid. Phases out at higher incomes. See student loan interest deduction.

4. Self-Employment Tax Deduction

Self-employed individuals deduct 50% of their self-employment tax (the employer-equivalent portion of FICA). This is automatic on your return.

5. Self-Employed Health Insurance Premiums

If you are self-employed and not eligible for an employer plan, you can deduct 100% of health, dental, and long-term care insurance premiums.

6. Self-Employed Retirement Contributions

Contributions to a Solo 401(k) or SEP IRA are deductible above the line, with generous limits (up to $72,000 for 2026 for a Solo 401(k)).

7. Educator Expenses

K-12 teachers can deduct up to $300 of unreimbursed classroom supplies without itemizing.

8. Alimony Payments (Pre-2019 Agreements)

If your divorce agreement was finalized before 2019, alimony payments are deductible by the payer and taxable to the recipient.

Itemized Deductions (Schedule A)

These deductions are only beneficial if your total exceeds the standard deduction. For 2026, that is estimated at $15,400 (single) or $30,800 (MFJ).

9. State and Local Taxes (SALT)

Deduct up to $10,000 in state income tax (or sales tax) plus property taxes. The $10,000 SALT cap applies through at least 2025; check legislative updates for 2026. See our full Schedule A itemized deductions guide for more details.

10. Mortgage Interest

Deduct interest on up to $750,000 of mortgage debt ($375,000 if married filing separately) for your primary residence and one second home.

11. Charitable Contributions

Cash donations to qualified charities, up to 60% of AGI. Donating appreciated stock avoids capital gains and generates a deduction at fair market value.

12. Medical and Dental Expenses

Deduct medical expenses exceeding 7.5% of your AGI. This can be significant in years with major surgery, dental work, or long-term care. Pairing with an HSA or FSA can further reduce out-of-pocket medical costs.

13. Casualty and Theft Losses

Deductible only if due to a federally declared disaster (post-TCJA).

Self-Employed Deductions

If you are self-employed, a freelancer, or run a side business, these Schedule C deductions reduce both income tax and self-employment tax:

14. Home Office Deduction

The simplified method allows $5 per square foot (up to 300 sq ft = $1,500). The regular method lets you deduct actual proportionate expenses. See our home office deduction guide.

15. Vehicle and Mileage

Deduct business miles at the IRS standard mileage rate (67 cents per mile for 2024; check for 2026 updates) or actual vehicle expenses. See best mileage apps.

16. Business Insurance

Deduct premiums for liability, malpractice, E&O, and workers’ compensation insurance.

17. Professional Services

CPA fees, legal fees, and consulting fees related to your business are deductible.

18. Business Equipment (Section 179)

Deduct the full cost of equipment and software in the year purchased, up to the Section 179 limit. Business vehicles have specific limits.

19. Continuing Education

Courses, certifications, and training that maintain or improve skills in your current business are deductible.

20. Business Travel and Meals

Deduct 100% of business travel costs (airfare, hotel, car rental). Business meals are 50% deductible.

Investment and Retirement Deductions

21. Capital Losses

You can offset capital gains with capital losses, plus deduct up to $3,000 of net losses against ordinary income per year. Unused losses carry forward indefinitely. See tax loss harvesting.

22. Investment Interest Expense

If you borrow to invest (margin loans), the investment interest expense is deductible up to your net investment income.

23. IRA Contribution (Catch-Up)

If you are 50 or older, the extra IRA catch-up contribution ($1,100 additional for 2026) is often overlooked.

Family and Education Deductions

24. Dependent Care FSA

While technically a pre-tax benefit (not a deduction), contributing to a Dependent Care FSA excludes up to $5,000 of childcare costs from income — equivalent to a deduction.

25. 529 Plan State Tax Deduction

Many states offer a state income tax deduction for 529 plan contributions. This is not a federal deduction, but can be valuable depending on your state. Starting in 2024, unused 529 funds can be rolled into a Roth IRA under certain conditions.

Tax Breaks You Might Be Missing

If you are a W-2 employee, do not assume you have no planning options. Above-the-line deductions, energy efficiency credits, education credits, and the Saver’s Credit are all available regardless of employment type. For a broader planning approach, see tax planning for W-2 earners.

Strategic Deduction Timing: Bunching

If your itemized deductions are close to the standard deduction threshold, consider charitable bunching — concentrating two years of charitable gifts into one year to exceed the threshold, then taking the standard deduction in the off year.

How sharper.tax Helps

sharper.tax analyzes your uploaded tax return and identifies deductions you may be missing — from overlooked above-the-line deductions to itemization strategies. We compare your deduction profile against peers in your income bracket to flag opportunities. Sophisticated tax planning used to require a high-end CPA — we make it available for free.

Sources

The information above is educational and not tax advice.