If you didn't apply for financial aid this year, but next year you need it, can you apply then?

I didn’t apply for financial aid this year because I (perhaps wrongly) assumed I would not get it and because my employer is paying part of the tuition. In fact today was the first day I used a financial aid calculator at one school and was surprised the number of families with six figure incomes who receive FA.

Question - Can you apply for financial aid after your kid is already at a particular school? And if so, must there be a change of family circumstances (sibling in college, loss of a job, etc) or can you just apply for no reason and see what happens?

Nothing can stop you from applying, but unless you can document a serious and significant change in your family’s financial situation (death, long-term unemployment prospects), it will be for naught. Students accepted as full-pay are expected to be full-pay for the duration of their BS stint.