diff --git a/src/USER-REAXC/fix_qeq_reax.cpp b/src/USER-REAXC/fix_qeq_reax.cpp
index 6a2bba5d8e..102faab8bc 100644
--- a/src/USER-REAXC/fix_qeq_reax.cpp
+++ b/src/USER-REAXC/fix_qeq_reax.cpp
@@ -401,6 +401,9 @@ void FixQEqReax::pre_force(int vflag)
   if (update->ntimestep % nevery) return;
   if( comm->me == 0 ) t_start = MPI_Wtime();
 
+  if (domain->xprd < swb || domain->yprd < swb || domain->zprd < swb) 
+    error->warning("FixQEqReax cutoff greater than periodic dimension");
+
   n = atom->nlocal;
   N = atom->nlocal + atom->nghost;
   // grow arrays if necessary
diff --git a/src/USER-REAXC/pair_reax_c.cpp b/src/USER-REAXC/pair_reax_c.cpp
index aaf517f768..d13fef914b 100644
--- a/src/USER-REAXC/pair_reax_c.cpp
+++ b/src/USER-REAXC/pair_reax_c.cpp
@@ -27,6 +27,7 @@
 #include "fix.h"
 #include "fix_reax_c.h"
 #include "memory.h"
+#include "domain.h"
 #include "error.h"
 
 #include "reaxc_types.h"
@@ -378,6 +379,9 @@ void PairReaxC::compute(int eflag, int vflag)
   double evdwl,ecoul;
   double t_start, t_end;
 
+  if (domain->xprd < cutmax || domain->yprd < cutmax || domain->zprd < cutmax) 
+    error->warning("PairReaxC cutoff greater than periodic dimension");
+
   // communicate num_bonds once every reneighboring
   // 2 num arrays stored by fix, grab ptr to them