Schedule A is the IRS form you attach to Form 1040 to claim itemized deductions, meaning you list individual deductible expenses like mortgage interest, state and local taxes, medical bills, and charitable donations to lower your taxable income instead of taking the flat standard deduction. It only pays off when those expenses add up to more than the standard deduction, which for the 2026 tax year is $16,100 for single filers, $32,200 for married couples filing jointly, and $24,150 for heads of household.1Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026 The One Big Beautiful Bill Act reshaped several Schedule A categories starting in 2026, most notably raising the cap on state and local tax deductions and making the current mortgage interest limit permanent.
When Itemizing Is Worth It
Every filer picks one of two options: the standard deduction, or the sum of qualifying expenses on Schedule A. Whichever is larger goes on your return. If your mortgage interest, property taxes, charitable giving, and out-of-pocket medical costs don’t clear the standard deduction for your filing status, the standard deduction wins with less paperwork.
Homeowners in high-tax states, people with major medical expenses, and large charitable donors are the filers who most often come out ahead by itemizing. The math shifts year to year as expenses, income, and inflation-indexed thresholds change, so run both calculations each filing season before deciding.
Medical and Dental Expenses
Unreimbursed medical and dental costs are deductible, but only the portion above 7.5% of your adjusted gross income.2Internal Revenue Service. Topic No. 502, Medical and Dental Expenses With an AGI of $80,000 and $9,000 in medical spending, the first $6,000 is off the table and only the remaining $3,000 is deductible. That threshold rules out most routine healthcare, so this line mainly helps people facing surgery, chronic illness, or expensive dental work.
Qualifying costs include doctor and hospital bills, prescription drugs, dental and vision care, hearing aids, mental health treatment, and health insurance premiums paid with after-tax dollars. Mileage to medical appointments counts at 20.5 cents per mile for 2026, plus parking and tolls.3Internal Revenue Service. IRS Sets 2026 Standard Mileage Rates Anything reimbursed by insurance or paid from an HSA doesn’t qualify; only true out-of-pocket spending does.4Internal Revenue Service. Publication 502, Medical and Dental Expenses
State and Local Taxes (SALT)
The SALT deduction covers taxes you already paid to state and local governments: property taxes plus either state income taxes or state sales taxes, but not both. For 2026, the cap is $40,400 for most filers and $20,200 if you’re married filing separately.1Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026 That’s well above the $10,000 cap that ran from 2018 through 2024.
High earners lose part of it. Once modified adjusted gross income passes $505,000 ($252,500 if married filing separately), the cap phases down by 30 cents for every dollar of income above the threshold, bottoming out at $10,000 around $606,333 of income. The cap rises 1% per year through 2029, then reverts to $10,000 in 2030.
In states with no income tax, deducting sales taxes usually makes more sense. The IRS provides an online calculator that estimates your sales tax deduction based on income, family size, and local rates, and you can add receipts for big purchases like a car or boat on top of that estimate.5Internal Revenue Service. Use the Sales Tax Deduction Calculator
Home Mortgage Interest
For mortgages taken out after December 15, 2017, you can deduct interest on up to $750,000 of acquisition debt ($375,000 if married filing separately). That limit is now permanent.6Internal Revenue Service. Publication 936, Home Mortgage Interest Deduction Older mortgages originated on or before that date keep the previous $1 million limit. Acquisition debt means the loan was used to buy, build, or substantially improve the home securing it.
Starting in 2026, mortgage insurance premiums on acquisition debt count as deductible mortgage interest, subject to an income-based phaseout. Your lender reports the interest paid on Form 1098, which you’ll use to fill in the mortgage line.7Internal Revenue Service. About Form 1098, Mortgage Interest Statement
Home equity loan interest is deductible only when the borrowed funds went into improving the home that secures the debt. A HELOC used for a kitchen renovation qualifies. The same loan used to pay off credit cards does not.
Charitable Contributions
Donations to qualified nonprofits are deductible, with limits tied to your AGI and the type of gift. Cash gifts to public charities can offset up to 60% of AGI. Donations of appreciated property held more than a year, like stock, are capped at 30% of AGI. Gifts to private foundations use lower ceilings. Anything you can’t use this year carries forward for up to five years.
Documentation scales with the size of the gift. Any single cash donation of $250 or more requires a written acknowledgment from the charity stating the amount and whether you received anything in return.8Internal Revenue Service. Charitable Organizations Substantiation and Disclosure Requirements Smaller cash gifts need a bank record or receipt. Noncash donations over $500 require Form 8283.9Internal Revenue Service. About Form 8283, Noncash Charitable Contributions
Noncash gifts over $5,000 (other than publicly traded stock) require an independent qualified appraisal and Section B of Form 8283. For deductions over $500,000, the appraisal itself has to be attached to the return.10Internal Revenue Service. Instructions for Form 8283 Skipping the appraisal or filing the wrong section can void the entire deduction, no matter how legitimate the gift.
Casualty and Theft Losses
Personal casualty and theft losses are deductible only when the damage stems from a federally declared disaster. State-declared disasters also qualify starting in 2026. Ordinary theft, a car accident, or storm damage in an undeclared area produces no deduction.11Internal Revenue Service. Publication 547, Casualties, Disasters, and Thefts
Two reductions apply before anything is deductible. Each separate casualty event is reduced by $100, and your combined casualty losses for the year must exceed 10% of AGI. With a $60,000 AGI, net losses (after insurance and the $100 reduction) need to top $6,000 before a dollar becomes deductible. Qualified disaster losses get more favorable treatment and skip the 10% AGI floor.
Investment Interest and Gambling Losses
Interest on money borrowed to buy taxable investments is deductible up to the amount of net investment income earned during the year.12Office of the Law Revision Counsel. 26 USC 163 – Interest Excess carries forward. Form 4952 walks through the calculation before the allowable amount lands on Schedule A. This line mostly matters for margin accounts and similar investment borrowing.
Gambling losses are deductible only up to the amount of gambling winnings reported as income.13Internal Revenue Service. Topic No. 419, Gambling Income and Losses Won $3,000 and lost $5,000 during the year? You deduct $3,000. The extra $2,000 can’t offset other income. A detailed log of sessions, dates, and amounts is what the IRS expects if it asks.
What You Can No Longer Deduct
Several items that used to sit on Schedule A are gone for good. The 2% miscellaneous itemized deductions, which once covered unreimbursed employee expenses, tax preparation fees, investment advisory fees, and similar costs, were suspended by the Tax Cuts and Jobs Act in 2018 and have now been eliminated.14Office of the Law Revision Counsel. 26 USC 67 – 2-Percent Floor on Miscellaneous Itemized Deductions Paying a CPA to prepare your return or buying a uniform your employer won’t reimburse doesn’t reduce taxable income through Schedule A anymore.
Moving expenses (except for active-duty military), hobby losses, and home office expenses for employees are also off the form.
The Married Filing Separately Trap
If you file as married filing separately and your spouse itemizes, you must itemize too.15Internal Revenue Service. Other Deduction Questions You can’t take the standard deduction, even if your itemized total is well below $16,100. Before choosing this filing status, run the numbers both ways, because forced itemization can wipe out whatever benefit prompted the separate return in the first place.
Separate filers also face tighter caps: SALT drops to $20,200, mortgage interest is limited to $375,000 of debt, and the SALT phasedown begins at $252,500 of income.
Documents to Gather Before You File
Schedule A works only when the numbers match paperwork. Pull these together before starting the form:
- Form 1098 from your mortgage lender, showing interest and any points paid.
- Property tax statements from your county or municipal tax authority.
- State income tax records: final pay stub or state W-2 showing total withholding, plus any estimated payments made during the year.
- Written acknowledgment letters from every charity where you gave $250 or more in a single donation.
- Medical bills, explanation-of-benefits forms, and receipts for out-of-pocket costs, organized by provider.
- Form 8283 for any noncash charitable contribution over $500, plus a qualified appraisal for gifts over $5,000.
Organize by category, not by date, because each line on Schedule A corresponds to a category. If the SALT decision between state income tax and state sales tax is close, gather records for both and use whichever produces the bigger deduction.
Filing and Keeping Records
Schedule A attaches to Form 1040. E-filing software transmits both together automatically. Paper filers place Schedule A directly behind the 1040.
Keep the filed Schedule A and every supporting document for at least three years from the filing date.16Internal Revenue Service. How Long Should I Keep Records That’s the standard IRS audit window. Underreporting income by more than 25% extends that window to six years, so hold documents longer if your return is complex. Digital copies are fine when they’re legible and backed up; a phone photo of a faded receipt is not much help years later.
State rules on itemization don’t always match federal. Some states require the same choice you made federally, others let you itemize on one return and take the standard deduction on the other. Check your state’s rules before assuming the federal choice carries over.