diff --git a/src/spicelib/devices/bsimsoi/b4soidest.c b/src/spicelib/devices/bsimsoi/b4soidest.c
index b3fb7c34f..c074941c7 100644
--- a/src/spicelib/devices/bsimsoi/b4soidest.c
+++ b/src/spicelib/devices/bsimsoi/b4soidest.c
@@ -24,6 +24,11 @@ B4SOIdestroy(GENmodel **inModel)
 {
     B4SOImodel *mod = *(B4SOImodel**) inModel;
 
+#ifdef USE_OMP
+    /* free just once for all models */
+    FREE(mod->B4SOIInstanceArray);
+#endif
+
     while (mod) {
         B4SOImodel *next_mod = B4SOInextModel(mod);
         B4SOIinstance *inst = B4SOIinstances(mod);