Self-compacting concrete (SCC) is an innovative concrete type requiring no compaction during placement. In the framework of this investigation, different quantities of fly ash (0, 30, 40, 50%) and limestone (0, 5%) were added to the concrete mixes. Self-compacting concrete properties were tested in the concretes’ fresh and hardened states (compressive strength, gas permeability, chloride ion diffusion), with fresh concrete properties enhanced through the addition of fly ash and limestone. The results suggest that the addition of fly ash and limestone has a positive effect on the durability of self-compacting concrete. Compressive strength values are lower with higher additions of these mineral additives. Based on the experimental results, an optimised composition of self-compacting concrete with fly ash and limestone can be recommended for practical application.