Itemizing deductions on Schedule A can potentially save you thousands in taxes—but it also opens the door to costly errors. Whether it’s overreporting charitable donations, misclassifying expenses, or simply failing to keep records, these mistakes can trigger audits or reduce your refund. Here’s a detailed look at the most frequent pitfalls taxpayers make when itemizing deductions on their 2025 federal return—and how to avoid them.
📄 1. Failing to Keep Adequate Documentation
The IRS requires that you maintain proper receipts, statements, and acknowledgment letters for many deductions, especially for:
- Charitable donations over $250 (must include a written acknowledgment from the organization)
- Medical expenses (invoices, payment records, mileage logs)
- Mortgage interest (Form 1098 or equivalent statement)
Tip: Create a digital folder for each deduction category and store PDF copies or scanned receipts throughout the year.
🔁 2. Double-Dipping on Deductions
You can’t deduct the same expense twice. Common double-dipping issues include:
- Claiming home office expenses and also deducting the full cost of home utilities elsewhere
- Reporting mortgage interest on both Schedule A and a rental property Schedule E if the property is used personally and as a rental
- Using HSA or FSA funds to pay for medical expenses and then also deducting those same expenses on Schedule A
Tip: Ensure each expense is allocated to only one tax treatment area.
💸 3. Deducting Non-Qualified Charitable Contributions
Only donations made to IRS-qualified 501(c)(3) organizations are deductible. Mistakes include:
- Donating to a GoFundMe campaign or individual person (not deductible)
- Claiming the full value of goods donated without reducing for fair market value (e.g., used clothing)
- Failing to reduce cash donations by the value of gifts received (e.g., deducting $100 when you received a tote bag in return)
Tip: Use the IRS’s Tax-Exempt Organization Search tool to verify charities before donating.
🏠 4. Misreporting Mortgage Interest or Property Taxes
If you own multiple homes or have refinanced, it’s easy to make mistakes:
- Claiming interest on a loan not secured by the home
- Deducting prepaid interest or points that should be amortized over the life of the loan
- Deducting foreign property taxes (not allowed under TCJA for personal residences)
Tip: Carefully read your Form 1098 and make sure the interest is qualified acquisition debt.
🏥 5. Overestimating Medical Expense Deductions
Medical expenses are only deductible to the extent they exceed 7.5% of your Adjusted Gross Income (AGI). Common mistakes include:
- Including over-the-counter medications (not deductible unless prescribed)
- Claiming cosmetic procedures not deemed medically necessary
- Including premiums paid with pre-tax dollars (e.g., from employer plans)
Tip: Review IRS Publication 502 for a full list of deductible and non-deductible medical expenses.
🏛️ 6. Ignoring the SALT Deduction Cap
Many taxpayers mistakenly try to deduct more than the legal limit of state and local taxes:
- $10,000 cap for state/local income, property, and sales taxes combined ($5,000 if MFS)
- Prepaying property taxes may not help if they’re not assessed before year-end
Tip: Use IRS guidance to determine what counts as assessed taxes for prepayment eligibility.
🛑 7. Itemizing When It Doesn’t Help
Some taxpayers continue to itemize out of habit, even when the standard deduction is higher. For 2025, the standard deduction is:
- $15,750 for Single
- $31,500 for Married Filing Jointly
- $23,300 for Head of Household
Tip: Compare your Schedule A total to your standard deduction before finalizing your return.
📋 Other Common Errors
- Forgetting to carry over prior-year contributions limited by AGI rules
- Misclassifying employee business expenses (most are no longer deductible unless you’re in a special occupation)
- Failing to prorate deductions when married filing separately or when using the foreign earned income exclusion
✅ Summary
Schedule A can be a valuable tool for reducing your taxable income—but only when used correctly. Avoid these common mistakes to ensure you’re maximizing your deductions without risking IRS scrutiny. When in doubt, consult a tax professional or use tax preparation software with built-in audit alerts and deduction checklists.
Need help reviewing your itemized deductions before filing? Upload your summary or totals, and we’ll check them for compliance and accuracy.
