diff --git a/src/cosmology.c b/src/cosmology.c
index a39efc6055330292d879450fbfe0f3fb61585610..0ee76dd79978586c2799cb786dd8bca4b96cc1cd 100644
--- a/src/cosmology.c
+++ b/src/cosmology.c
@@ -497,6 +497,7 @@ void cosmology_init_no_cosmo(struct cosmology *c) {
 
   c->H = 0.;
   c->a = 1.;
+  c->z = 0.;
   c->a_inv = 1.;
   c->a2_inv = 1.;
   c->a3_inv = 1.;