Spending and Tax Limitation Act of 1979

Amends the Budget and Accounting Act, 1921 to require the President to submit an alternate budget to the Congress if the 1982 fiscal year budget sets forth estimated expenditures or estimated receipts in excess of 20.5 percent of the gross national product. Requires such an alternate budget if the level of expenditures or receipts exceeds 20 percent of the gross national product in any fiscal year thereafter.

Amends the Congressional Budget Act of 1974 to direct the Budget Committees of the House of Representatives and the Senate to report such an alternate budget with the concurrent resolution on the budget for fiscal year 1982 and thereafter if the reported levels of outlays or revenues exceed the percentages of the gross national product set forth above. Requires the accompanying report to explain the differences between the alternate and the budget resolution. Requires the Congress to consider the alternate budget resolution separately, and before the concurrent resolution for which it is an alternate.