Creates a new rule in the Stafford Act that defines “excess funds for management costs” and lets the President direct those excess funds to grantees or subgrantees. The money can be used for management costs tied to disasters, emergencies, preparedness measures, or certain mitigation activities and for building preparedness, recovery, or mitigation capacity; funds made available remain available for five years. The bill also requires a GAO report within 180 days on actual management costs during major disaster declarations and specifies that no new appropriations are authorized to implement the change.