Helping Students Plan for College Act of 2021 This bill requires certain statements related to the impact of nonfederal financial assistance (e.g., private scholarships, grants, and loans) on financial-aid awards from an institution of higher education (IHE). Specifically, the bill requires an IHE that participates in federal student-aid programs and adjusts its financial-aid awards based on students receiving such other financial assistance to provide enrolled and prospective students with a statement about (1) its policies on adjusting awards, and (2) how receipt of such other financial assistance may impact student eligibility for and the amount of financial-aid awards from the IHE. The Government Accountability Office must study and report on the relationship between such other financial assistance and eligibility for and the amount of financial-aid awards from IHEs.