Breeding blankets are of interest for a sodium fast reactor (SFR) as they allow for small cores to have positive breeding gains. However, because they breed very high-quality plutonium, core designers are not currently encouraged to employ blankets. After verifying that the ERANOS code was in good agreement with BGcore, a Monte Carlo-based depletion system, it was shown that an SFR blanket design could breed less attractive plutonium than light water reactor (LWR)-bred plutonium for making a nuclear explosive device. Minor actinide (MA) doping and moderator addition were the two options studied. This study shows that it is possible to build an SFR with a secure blanket with MA addition; at steady state MAs from approximately 1.5 LWRs are required per SFR [both rated at 1 GW(electric)].