The cowpea aphid, Aphis craccivora Koch (Homoptera: Aphididae) is a serious insect pest that infests legume crops. Flupyradifurone (FPF) is a butenolide insecticide that selectively targets sucking insects including aphids and whiteflies. However, the realized heritability (h2) and fitness costs associated with resistance to FPF have not yet been assessed with A. craccivora. In this study, A. craccivora showed the potential to develop resistance to FPF under continuous selection, with an overall mean estimated h2 of resistance of 0.21. Results of fitness costs showed no differences in the developmental time (except for N2 and N3), longevity, fecundity, adult pre-reproductive period (APRP), total pre-reproductive period (TPRP), and oviposition of the FPF-R strain compared to the S-strain. In contrast, all population growth parameters, including the growth reproductive rate (GRR), net reproductive rate (R0), intrinsic rate of increase (r), finite rate of increase (λ), mean generation time (T), and doubling time (DT), were significantly lower in the FPF-R strain than in the S-strain. Fitness cost studies revealed that resistance to FPF decreased the relative fitness of the FPF-R strain to 0.76 compared with that of the S-strain. The estimation of realized heritable h2 and identification of resistance fitness costs provide a basis for designing insecticide resistance management (IRM) programs to sustain susceptibility in insect populations.