A balanced budget amendment (BBA) would require federal outlays in each fiscal year to not exceed revenues, typically with carve-outs for declared war, natural disaster, or supermajority votes in both chambers. Various BBA proposals have come close to congressional passage; an Article V state-led convention drive has also pursued one. Most U.S. states have a balanced-budget requirement in their own constitutions for ordinary spending.
Proponents argue the federal government's chronic deficits — and the resulting national debt — pose long-term fiscal risk that ordinary political processes cannot discipline. A constitutional rule would force trade-offs that Congress avoids and shift the political default from borrowing to choosing.
Opponents argue that a BBA would force pro-cyclical fiscal policy — cutting spending and raising taxes in recessions when the opposite is needed — and that essential automatic stabilizers (unemployment insurance, SNAP, Medicaid) would be among the first casualties. Many economists oppose the idea on macroeconomic grounds even if they favor lower long-run deficits.