Tensile, creep, and automated ball indentation (ABI) tests have been conducted to study deformation mechanisms in Sn5%Sb alloy between ambient and 473 K. A power law relationship was obtained between minimum creep rate and applied stress, with stress exponent, n=5 and activation energy, Q=12.6± 1.1 kCal/mole. At 473 K, a transition from n=5 to n=3 was observed at low stresses. ABI tests showed a power law relationship between strain rate and ultimate tensile stress with values of n=5 and Q=13.0± 1.8 kCal/mole. Tensile results were in broad agreement with the creep and ABI data. A new deformation mechanism is pro­posed for the n=5 region involving viscous glide of dislocations assisted by dislocation core diffusion.