Decrease Spending Now Act - Rescinds $45 billion of unobligated balances of current discretionary appropriations.

Requires the Director of the Office of Management and Budget (OMB) to: (1) determine which appropriation accounts the rescission shall apply to and the amount that each such account shall be reduced, and (2) report to the Secretary of the Treasury and Congress a list of the accounts reduced by the rescission, including the amounts rescinded from each such account.

Exempts from such rescission the Department of Defense (DOD), the Department of Veterans Affairs (VA), and the Social Security Administration (SSA).