The FAFSA is the federal form. It determines Pell Grants, federal loans and work-study, and nearly every state and public university uses it. It opens October 1 and is free.
The CSS Profile
About 200 mostly private colleges also require the CSS Profile, which asks more detailed questions about assets, home equity and non-custodial parents. It charges a fee, waived for low-income families.
Deadlines are the trap
Each college sets its own priority deadline, often November or December for early applicants. Aid awarded after priority deadlines comes from whatever is left. File both forms as soon as they open, using estimates if needed, and correct them later.
Special circumstances
If income dropped after the tax year the forms use, write to each aid office with documentation. Offices can and do adjust.