SBP Benefits Improvement Act of 2003

SBP Benefits Improvement Act of 2003 - Amends Federal provisions concerning the military Survivor Benefit Plan (SBP) to adjust the basic SBP annuity amount for surviving spouses age 62 or over of former military personnel to: (1) 35 percent of the retired pay of the decedent, for months beginning on or before the enactment of this Act (current law); (2) 40 percent of such pay, for months beginning after such date and before October 2007; (3) 45 percent, for months beginning after September 2007; and (4) 55 percent, for months beginning after September 2013.

Adjusts similarly the authorized percentage amounts of SBP supplemental annuity authorized for such spouses.

Directs the Secretary of Defense to ensure appropriate adjustments in the computation of retired pay deductions for such supplemental annuities made necessary by this Act.