Line-by-Line Guide to Form 1040 (2024)

Form 1040 is the central document of your tax return. For the 2024 tax year (filed in 2025), the form remains two pages, but understanding what goes where is crucial to avoiding IRS notices.

Income Section (Lines 1-9)

This is where you report money you've made. For most people, this starts with their W-2.

Line 1: Total amount from Form(s) W-2, box 1

Add up the amounts from Box 1 of every W-2 you received this year. Do not include 1099 income here.

Line 2: Tax-exempt and taxable interest

2a (Tax-exempt): Report interest from municipal bonds.
2b (Taxable): Report interest from bank accounts, found in Box 1 of Form 1099-INT.

Line 3: Dividends

Found on Form 1099-DIV. Qualified dividends (3a) are taxed at lower capital gains rates.

Deductions (Lines 12-14)

This section reduces your taxable income.

Line 12: Standard Deduction or Itemized Deductions

Most taxpayers take the standard deduction. If your itemized deductions (medical expenses, mortgage interest on Form 1098, state taxes) exceed the standard amount, use Schedule A.

Common Mistakes

• Math errors: Double-check addition, especially when transferring numbers from schedules.
• Missing signatures: Both spouses must sign a joint return.
• Wrong routing numbers: Verify your bank details for direct deposit.