What information is required to fill out the Free Application for Federal Student Aid (FAFSA®) form?

https://studentaid.gov/help-center/answers/article/what-info-do-i-need-to-fill-out-fafsa

Gathering the Documents Needed to Apply

The FAFSA questions ask for information about you (your name, date of birth, address, etc.) and about your financial situation. Depending on your circumstances (for instance, whether you’re a U.S. citizen or what tax form you used), you might need the following information or documents as you fill out the FAFSA application:

• Your Social Security number (it’s important that you enter it correctly on the FAFSA form!)

• Your parents’ Social Security numbers if you are a dependent student

• Your driver’s license number if you have one

• Your Alien Registration number if you are not a U.S. citizen

• Federal tax information or tax returns including IRS W-2 information, for you (and your spouse, if you are married), and for your parents if you are a dependent student:

  • IRS 1040

  • Foreign tax return or IRS 1040NR

  • Tax return for Puerto Rico, Guam, American Samoa, the U.S. Virgin Islands, the Marshall Islands, the Federated States of Micronesia, or Palau

• Records of your untaxed income, such as child support received, interest income, and veterans noneducation benefits, for you, and for your parents if you are a dependent student

• Information on cash; savings and checking account balances; investments, including stocks and bonds and real estate (but not including the home in which you live); and business and farm assets for you, and for your parents if you are a dependent student

From: https://studentaid.gov/apply-for-aid/fafsa/filling-out#gathering-the-documents-needed-to-apply