Financial Glossary
Schedule A (Form 1040) — Itemized Deductions
Schedule A is the attachment to Form 1040 that allows individual taxpayers to itemize deductions instead of claiming the standard deduction. Itemized deductions may include state and local taxes paid (subject to a cap), mortgage interest on a primary and secondary residence, charitable contributions, and certain casualty losses. A taxpayer itemizes only when total qualifying deductions exceed the applicable standard deduction, which depends on filing status and is adjusted annually. The choice between itemizing and taking the standard deduction is made each tax year.
Problem & Application
The most common mistake individuals make with Schedule A is assuming they should itemize because they have a mortgage. With standard deduction amounts at their current levels, a large percentage of taxpayers -- including many homeowners -- actually come out ahead taking the standard deduction. Conversely, taxpayers with significant charitable giving, high state income or property taxes, or substantial mortgage interest may leave meaningful deductions on the table by defaulting to the standard. Documentation requirements are strict -- charitable contributions above certain thresholds require written acknowledgment, and undocumented deductions are disallowed at audit.
In Short
The deduction choice on Schedule A is binary but the math is not obvious. Running both calculations every year and maintaining proper documentation for itemized categories is the only way to ensure you are not overpaying.