📋 Table of Contents
How the Deduction Choice Works
After you calculate your total (gross) income, you're allowed to subtract deductions before arriving at taxable income — the amount your tax bracket actually applies to. Every filer picks one of two paths for this subtraction:
- Standard deduction: a flat dollar amount based solely on your filing status (single, married filing jointly, married filing separately, head of household), adjusted upward slightly most years for inflation. No receipts, no itemizing — just claim the number.
- Itemized deductions: you total up specific allowed expenses (mortgage interest, state/local taxes up to a cap, charitable gifts, large medical costs, etc.) on Schedule A, and that total replaces the standard deduction if it's larger.
You cannot do both — it's one or the other, whichever produces the bigger deduction (and therefore the lower tax bill).
The Standard Deduction
The standard deduction roughly doubled starting with the 2018 tax year under the Tax Cuts and Jobs Act, and has been adjusted for inflation in most years since, with further legislative changes affecting exact amounts in subsequent years. As a result, it now typically sits in the five-figure range for single filers and roughly double that for married couples filing jointly — high enough that a large majority of US households no longer have enough itemizable expenses to exceed it. Filers 65 or older, or who are blind, are generally allowed an additional standard deduction amount on top of the base figure.
What You Can Still Itemize
Itemized deductions reported on Schedule A generally fall into these main categories:
| Category | What It Covers |
|---|---|
| State and local taxes (SALT) | State/local income or sales tax, plus property tax — subject to an annual cap |
| Mortgage interest | Interest on a qualifying home mortgage, up to certain loan-balance limits |
| Charitable contributions | Cash and property donations to qualifying charitable organizations, subject to income percentage limits |
| Medical and dental expenses | Unreimbursed costs above a threshold percentage of adjusted gross income (AGI) |
| Casualty and theft losses | Generally limited to federally declared disaster areas under current law |
Note that several deductions that existed before 2018 — including unreimbursed employee business expenses and most miscellaneous itemized deductions subject to the old 2%-of-AGI floor — were suspended by the 2017 tax law changes and, absent further legislation, remain unavailable for most individual filers.
The SALT Cap
The SALT (state and local tax) deduction — covering state/local income or sales tax plus property tax combined — was capped starting in 2018, a significant change from the previously unlimited deduction. The cap has been a recurring subject of legislative debate and adjustment in the years since; confirm the current cap amount for the tax year you're filing, since it directly affects whether itemizing makes sense for homeowners in high-tax, high-property-value states.
The SALT cap disproportionately affects itemizers in states with high property values and/or high state income tax rates, since it's often the largest single itemized category for homeowners — capping it was one of the biggest factors pushing many prior itemizers below the standard deduction threshold after 2018.
Mortgage Interest Deduction
Interest paid on a mortgage used to buy, build, or substantially improve your primary (or a second) home is deductible up to certain loan-balance limits set by law (limits are lower for mortgages taken out after the 2017 law changes than for older "grandfathered" loans). For most homeowners with a typical mortgage balance, this remains one of the largest potential itemized deductions — but its actual value depends on how much interest you're paying in a given year, which declines over the life of the loan as more of each payment goes to principal.
Charitable Contributions
Cash and property donations to IRS-qualified charitable organizations are deductible if you itemize, generally subject to a cap expressed as a percentage of your adjusted gross income (the specific percentage varies by the type of donation and recipient organization). Keep receipts and, for non-cash donations above certain thresholds, formal appraisals or written acknowledgments — the IRS requires documentation to support charitable deductions if audited.
Medical Expense Deduction
Unreimbursed medical and dental expenses are deductible only for the portion that exceeds a threshold percentage of your adjusted gross income (commonly 7.5% of AGI in recent years, though confirm the current-year threshold). This high floor means medical expenses rarely tip the scales toward itemizing unless you had an unusually expensive medical year — a major surgery, long-term care costs, or similar large unreimbursed bills.
The Simple Decision Test
- Add up your realistic itemizable expenses: mortgage interest + SALT (capped) + charitable gifts + medical expenses above the AGI threshold.
- Compare that total to your filing status's current-year standard deduction amount.
- Claim whichever number is larger — there's no benefit or penalty to either choice beyond the dollar amount itself.
Worked Example
A married couple filing jointly has $9,000 in mortgage interest, $8,000 in property tax (SALT capped, so only a portion may count depending on the current-year cap and any state income tax already counted against it), and $3,000 in charitable donations:
| Item | Amount |
|---|---|
| Mortgage interest | $9,000 |
| SALT (capped — illustrative, confirm current cap) | $8,000 or capped amount, whichever is lower |
| Charitable donations | $3,000 |
| Illustrative itemized total | ~$20,000 (before applying the current SALT cap precisely) |
Whether this couple should itemize depends entirely on comparing that total to the current-year married-filing-jointly standard deduction — since standard deduction amounts have risen substantially since 2018, run your own real numbers through a current-year comparison rather than assuming itemizing automatically wins with numbers in this range.
Recent Legislative Context
Tax law affecting the standard deduction and itemized deductions has changed more than once in recent years, and further changes are always possible through new legislation. The 2017 Tax Cuts and Jobs Act (effective starting the 2018 tax year) was the single biggest shift: it roughly doubled the standard deduction, capped the SALT deduction, suspended most miscellaneous itemized deductions, and lowered the mortgage-interest loan-balance limit for new loans — many of these provisions were originally written as temporary and scheduled to expire, which created significant uncertainty in the years since about which rules would remain in place. Subsequent legislation has extended, modified, or made permanent various pieces of this framework. Because of this ongoing legislative activity, treat any specific dollar figure you read (including in this guide) as illustrative of the general structure rather than a guaranteed current-year number, and always verify directly with the IRS or a tax professional for the year you're actually filing.
Common Itemizing Mistakes
- Forgetting to include out-of-state or prior-home property tax paid mid-year when moving, which still counts toward the SALT total for the year it was paid.
- Double-counting a deduction already taken elsewhere — for example, mortgage interest on a home office already partially deducted as a business expense shouldn't also be fully claimed again on Schedule A.
- Missing the AGI threshold on medical expenses — only the portion of medical expenses above the threshold percentage of AGI counts, not the full amount spent, which trips up filers who assume their entire medical bill is deductible.
- Not keeping adequate charitable-donation documentation — cash donations generally need a receipt or bank record, and non-cash donations above certain thresholds require additional documentation or a qualified appraisal.
- Assuming last year's decision (standard vs itemized) automatically applies again this year — a change in mortgage balance, a move, a big charitable gift, or an unusually high medical-expense year can flip which option is larger from one year to the next.