What the form does with what you give it. The FAFSA collects identity, family and financial information and produces a single number, the Student Aid Index, which colleges then use to build an aid package. That number replaced the Expected Family Contribution beginning with the 2024-25 award year, and the change was more than cosmetic: the Index is explicitly an index rather than an estimate of what a family will pay, and it can be negative. Anyone who filed before 2024-25 and remembers an "EFC" is looking for the same slot in the process under a new name. The old label also survives in places the rename never reached, including parts of the Education Department's own loan regulations, so encountering "EFC" in an official document is not evidence that it still governs.
Income comes from two years back, and it comes from the IRS. The statute defines the relevant adjusted gross income as that of the second tax year preceding the academic year, so a form for the 2026-27 year uses 2024 income. This has a useful consequence and an awkward one: the numbers are already final when the form is filed, and a family whose income has since collapsed is being assessed on a year that no longer describes them. The form itself discloses that a case-by-case adjustment is available for exactly that situation. Under the FUTURE Act the tax data is transferred directly from the Internal Revenue Service rather than typed in, which is why consent is now a structural part of the process rather than a checkbox.
The contributor model is where most filings stall. The Education Department uses contributor to mean anyone required to provide information on the form: the student, the student's spouse, a biological or adoptive parent, or that parent's spouse, depending on dependency status. Each contributor needs their own account and must give their own consent to the tax-data transfer, and because the application is made for a single award year, the consents are given again for each new one. That consent is not a courtesy. Under 20 U.S.C. 1098h the Secretary must require approval "as a condition of eligibility" for federal aid, and must warn applicants that without it the Department will be "unable to calculate eligibility". So if a required contributor never consents, the form cannot establish federal aid eligibility for that year, which means one person's inaction can decide the outcome for someone else.
Two 2026 changes that make filing matter more, not less. Public Law 119-21 added a hard eligibility ceiling for Pell Grants effective 1 July 2026: a student whose Student Aid Index equals or exceeds twice the total maximum Pell Grant for that year is ineligible, regardless of the other tests that used to decide the question. The same Act added foreign income to adjusted gross income for Pell determinations from the same date. Both operate on the number the FAFSA produces, so both are reasons to understand the output rather than treat the form as a formality.