The relative fixity of a digraph $Γ$ is defined as the ratio between the largest number of vertices fixed by a nontrivial automorphism of $Γ$ and the number of vertices of $Γ$. We characterize the vertex-primitive digraphs whose relative fixity is at least $1/3$, and we show that there are only finitely many vertex-primitive digraphs of bounded out-valency and relative fixity exceeding a positive constant.