Binary neutron star ( BNS ) mergers are one of the proposed origins for both repeating and non-repeating fast radio bursts ( FRBs ) , which associates FRBs with gravitational waves and short gamma-ray bursts ( GRBs ) . In this work , we explore detectability of radio counterparts to an FRB by calculating the radio afterglow flux powered by the two components : a relativistic jet and a slower isotropic ejecta from a BNS merger . Detection probability of a radio afterglow for a FRB is calculated as a function of the source redshift , observing time , and flux sensitivity , assuming that FRBs are not strongly beamed . The model parameter distributions inferred from short GRB afterglows are adopted . We find that the detection probability for an FRB at z = 0.5 is 3.7 and 4.1 % for the jet and isotropic components , respectively , when observed at the timing of their peak flux ( \sim 10 days and 1 year ) with a typical sensitivity of 10 \mu Jy . The probability increases to 10 and 14 % , respectively , with \sim 1 \mu Jy sensitivity achievable with future facilities ( e.g . SKA ) . In particular for the repeating FRB 180916.J0158+65 , we find a high chance of detection ( 60 % at 10 \mu Jy sensitivity ) for the isotropic component that would peak around \sim 10 years after the merger , as a natural consequence of its close distance ( z = 0.03 ) . Therefore a long term radio monitoring of persistent radio emission for this object is important . The detection probability is similar for the jet component , though the peak time ( \sim 200 days ) has likely already passed for this FRB .