Stress rupture tests on smooth and notched tensile bars and creep crack growth measurements under both static and cyclic loading have been made on virgin (new) solution annealed and naturally aged Type 304H stainless steel at 760C. The naturally aged material was taken from a component which had been in service for 15 years at temperatures in the range 690 to 725C. It is known that some deterioration in properties occurs with aging in Type 304 stainless steel and that this could affect sensitivity to cracking. This paper shows that crack growth rate can be characterized in terms of the creep fracture mechanics parameter C* and that the behavior of the new and aged materials can be rationalized in terms of their creep ductilities and the influence of ductility on the state of stress developed at a crack tip. Furthermore, the paper demonstrates that lower and upper bound crack growth rates can be estimated approximately from uniaxial creep rupture data.