The Basics: Standard vs. Itemised
Every year when you file your federal income tax return, you face a choice: take the standard deduction - a flat dollar amount set by the IRS based on your filing status - or itemise, meaning you list out specific qualifying expenses one by one on Schedule A. You can do one or the other, never both.
The standard deduction is straightforward. For most filers, it wipes out a meaningful chunk of income without any paperwork. Itemising, by contrast, requires documentation and effort, but can produce a larger deduction if your qualifying expenses are high enough. To understand how deductions fit into the broader picture of reducing your tax bill, see our guide to deductions vs. credits.
It is also worth knowing that some valuable deductions - such as student loan interest and contributions to a traditional IRA - can be claimed without itemising at all. These are called above-the-line deductions. Learn more in our article on above-the-line deductions you can claim without itemising.
What You Can Actually Itemise
The IRS recognises a defined set of expenses on Schedule A. The most commonly claimed categories include:
- Mortgage interest: Interest paid on a qualified home loan, up to IRS limits. This is the single biggest driver of itemised returns for most filers.
- State and local taxes (SALT): A combination of state income or sales taxes and property taxes, currently capped at $10,000 per return.
- Medical and dental expenses: Only the portion that exceeds 7.5% of your adjusted gross income (AGI) qualifies. High out-of-pocket costs from a serious illness or surgery can push you past this threshold.
- Charitable contributions: Cash and non-cash donations to qualified organizations are deductible. Rules around documentation and limits are detailed - our guide to charitable giving and your taxes breaks down exactly what qualifies.
- Casualty and theft losses: Only losses from federally declared disasters generally qualify under current law.
Married Filing Separately Has Special Rules
If you are married filing separately, both spouses must make the same choice - either both itemise or both take the standard deduction. If your spouse itemises, you are required to itemise as well, even if the standard deduction would otherwise be larger for you. This is an important planning consideration for couples filing separately.
Homeowners are the group most likely to benefit from itemising. If you own a home, consult our overview of home-related tax deductions to understand which housing costs may be deductible.
Pros and Cons of Itemising
Before committing to Schedule A, weigh these advantages and disadvantages honestly against your own situation.
Can produce a larger deduction than the standard amount
If your qualifying expenses are high - particularly mortgage interest and SALT - itemising may reduce your taxable income well beyond what the standard deduction allows, lowering your overall tax bill.
Captures real costs you've already paid
Rather than accepting a fixed allowance, itemising reflects what you actually spent. For filers with significant medical bills or large charitable contributions, this is a meaningful distinction.
Especially valuable for homeowners with large mortgages
Mortgage interest alone can push total deductions far above the standard threshold, making itemising the clearly superior choice for many homeowners in higher-cost housing markets.
Encourages disciplined year-round record keeping
Tracking deductible expenses throughout the year builds financial awareness and ensures you don't miss legitimate deductions when filing season arrives.
Most filers won't exceed the standard deduction
The 2017 Tax Cuts and Jobs Act roughly doubled the standard deduction, meaning a smaller share of taxpayers have enough qualifying expenses to make itemising worthwhile.
Requires extensive documentation and record keeping
Every deduction you claim must be substantiated with receipts, statements, or acknowledgment letters. Losing records mid-year can mean losing the deduction entirely.
The SALT cap limits a major deduction category
State and local taxes are capped at $10,000 per return, which significantly limits the benefit for filers in high-tax states who previously relied on this deduction heavily.
More complex and time-consuming to prepare
Filing Schedule A adds steps, calculations, and the risk of errors. Filers who make mistakes may face IRS correspondence or, in more serious cases, an audit.
Medical expenses face a high threshold to qualify
Only medical costs exceeding 7.5% of your AGI are deductible, which means routine healthcare expenses rarely generate a meaningful deduction for most taxpayers.
For a structured comparison of how to weigh these trade-offs against the standard deduction, see Standard Deduction vs. Itemising: Which Approach Suits Your Situation?.
How to Decide: A Practical Test
The decision comes down to one comparison: are your total qualifying expenses greater than the standard deduction for your filing status? If yes, itemising puts more money back in your pocket. If no, the standard deduction wins.
~11%
Share of US filers who itemise
According to IRS Statistics of Income data, the proportion of filers choosing to itemise dropped sharply after the 2017 increase to the standard deduction.
$10,000
Current SALT deduction cap per return
The Tax Cuts and Jobs Act imposed this cap on combined state and local income, sales, and property tax deductions, limiting a previously uncapped category.
Start by gathering your records - mortgage interest statements (Form 1098), property tax bills, medical receipts, and charitable contribution acknowledgments. Add them up. Then look up the current standard deduction for your filing status on the IRS website. If your total falls short, stop there and take the standard deduction. If it exceeds the standard deduction, itemising is likely the better route.
Also consider your time and complexity tolerance. Itemising correctly means keeping receipts all year, accurately categorising expenses, and potentially responding to IRS inquiries. If you find the process overwhelming, a qualified tax professional can help you determine the optimal approach for your circumstances.
For a fuller side-by-side walkthrough of both paths, see Standard Deduction or Itemising: How Filers Decide Between the Two.
This article is for general informational purposes only and does not constitute personalised tax or legal advice. Tax rules change frequently and vary by individual circumstances. Consult a qualified tax professional for guidance specific to your situation.
