Itemized Deduction

A specific deductible expense you list individually instead of taking the flat allowance.

Itemizing means listing qualifying expenses — mortgage interest, state and local taxes up to a cap, medical costs above a threshold, charitable donations — and subtracting the total from taxable income. It only pays when those expenses exceed the standard allowance, and it requires records for every claim. High-income households and homeowners in expensive areas are the most common itemizers.

Each itemized deduction has to be documented, so he kept every charity receipt from the year.