Titanium (Ti) and its alloys are among the desired materials for biomaterial, marine, and aerospace applications due to their excellent properties. Metastable beta titanium (β-Ti) alloys exhibit enhanced strengths and hardness values after thermomechanical processing (TMP) due to the presence of omega (ω) and alpha (α) phase precipitates in the beta (β) matrix. In this study, the creep properties of three different β-Ti alloys, Ti-12Cr-1Fe-3Al (wt. %), Ti-12Cr-3Al (wt. %), and T- 12Cr (wt. %), were experimentally obtained at different applied stresses and at 683 K. The relationship between microstructure and creep properties was investigated. X-ray diffractometer (XRD), optical microscope (OM), and scanning electron microscope (SEM) were used to help characterize the microstructure before and after creep deformation. The hardness of alloys increased after heat treatment for 48 hrs at 410 ºC due to the precipitation of the α and ω phases. The creep tests showed that Ti-12Cr-1Fe-3Al (wt. %) was the most creep resistant and Ti-12Cr (wt. %) was the least creep resistant.