Guard and Reserve Retirement Retainer Act of 2004 - Provides that, in the case of a person to whom the payment of military retired pay for non-regular (reserve) service commences after the person attains 55 years of age and before the person attains 60 years of age, the amount of such pay shall be reduced by: (1) 12.5 percent for age 55; (2) 9 percent for age 56; (3) 6 percent for age 57; (4) 3.5 percents for age 58; and (5) 1.5 percent for age 59.
Prohibits any such person from receiving medical and dental care through facilities of the Department of Defense until the person has attained 60 years of age.