For the 2019-2020 school year, the federal government's financial aid form, the FAFSA, can be filed as early as October 1, 2018. It relies on current asset information and two-year-old income information from your 2017 tax return, which means you'll have the income data you need when you sit down to complete the form. This is a relatively new process. A few years ago, parents had to wait until after January 1 to file the FAFSA and use tax data for the year that had just ended, which forced them to scramble to complete their tax return in order to complete the FAFSA.
If you have a new or returning college student, it's a good idea to file the FAFSA as early as possible in the fall because some aid programs operate on a first-come, first-served basis. The deadline for filing the FAFSA is typically March or April and will vary by college. But don't wait until then. It's a good idea to submit any college aid forms as early as possible, too.
The FAFSA is a prerequisite for federal student loans, grants, and work-study. In addition, colleges typically require the FAFSA before distributing their own need-based aid and, in some cases, merit-based aid. Even in cases when you don't expect your child to qualify for need-based aid, there may be another reason to submit the FAFSA. All students attending college at least half-time are eligible for federal unsubsidized Direct Loans regardless of financial need. ("Unsubsidized" means the borrower, rather than the government, pays the interest that accrues during school, the grace period after graduation, and any deferment periods.)
The FAFSA is available online at fafsa.ed.gov.