New fabrication techniques were developed for uniaxial creep specimens of high‐strength, high elastic modulus, pitch‐based, carbon filaments, with a matrix‐free test section. Experiments show that pitch‐based carbon filaments with a tensile modulus of 896 GPa can exhibit, under high stress, large creep deformation without necking. The stress exponent for the pitch‐based fibers in the Dorn equation is much lower than that for PAN‐based fibers, while the activation energy is the same. The activation energies and activation volumes determined from the experiments suggest mechanisms of creep