When should I itemize deductions instead of taking the standard deduction?

Itemize when your qualifying expenses exceed the standard deduction ($14,600 single / $29,200 married filing jointly for 2024). Common itemized deductions include mortgage interest, state/local taxes (SALT, capped at $10K), charitable donations, and medical expenses exceeding 7.5% of AGI. Most tax software automatically calculates which option saves you more.