diff --git a/src/MC/fix_gcmc.cpp b/src/MC/fix_gcmc.cpp
index 7da19241e9..ddafd33d84 100644
--- a/src/MC/fix_gcmc.cpp
+++ b/src/MC/fix_gcmc.cpp
@@ -718,6 +718,8 @@ void FixGCMC::attempt_atomic_translation()
         coord[2] = x[i][2] + displace*rz;
       }
     }
+    if (!domain->inside(coord)) 
+      error->one(FLERR,"Fix gcmc put atom outside box");
 
     double energy_after = energy(i,ngcmc_type,-1,coord);
     if (random_unequal->uniform() < 
@@ -805,6 +807,9 @@ void FixGCMC::attempt_atomic_insertion()
     coord[2] = zlo + random_equal->uniform() * (zhi-zlo);
   }
 
+  if (!domain->inside(coord)) 
+    error->one(FLERR,"Fix gcmc put atom outside box");
+
   int proc_flag = 0;
   if (coord[0] >= sublo[0] && coord[0] < subhi[0] &&
       coord[1] >= sublo[1] && coord[1] < subhi[1] &&
@@ -919,6 +924,8 @@ void FixGCMC::attempt_molecule_translation()
       coord[0] = x[i][0] + com_displace[0];
       coord[1] = x[i][1] + com_displace[1];
       coord[2] = x[i][2] + com_displace[2];
+      if (!domain->inside(coord)) 
+  	error->one(FLERR,"Fix gcmc put atom outside box");
       energy_after += energy(i,atom->type[i],translation_molecule,coord);
     }
   }
@@ -1002,6 +1009,8 @@ void FixGCMC::attempt_molecule_rotation()
       xtmp[1] = atom_coord[n][1];
       xtmp[2] = atom_coord[n][2];
       domain->remap(xtmp);
+      if (!domain->inside(xtmp)) 
+	error->one(FLERR,"Fix gcmc put atom outside box");
       energy_after += energy(i,atom->type[i],rotation_molecule,xtmp);
       n++;
     }
@@ -1121,6 +1130,8 @@ void FixGCMC::attempt_molecule_insertion()
     xtmp[1] = atom_coord[i][1];
     xtmp[2] = atom_coord[i][2];
     domain->remap(xtmp);
+    if (!domain->inside(xtmp)) 
+      error->one(FLERR,"Fix gcmc put atom outside box");
 
     procflag[i] = false;
     if (xtmp[0] >= sublo[0] && xtmp[0] < subhi[0] &&
@@ -1313,6 +1324,8 @@ void FixGCMC::attempt_atomic_translation_full()
         coord[2] = x[i][2] + displace*rz;
       }
     }
+    if (!domain->inside(coord)) 
+      error->one(FLERR,"Fix gcmc put atom outside box");
     xtmp[0] = x[i][0];
     xtmp[1] = x[i][1];
     xtmp[2] = x[i][2];
@@ -1426,6 +1439,9 @@ void FixGCMC::attempt_atomic_insertion_full()
     coord[2] = zlo + random_equal->uniform() * (zhi-zlo);
   }
   
+  if (!domain->inside(coord)) 
+    error->one(FLERR,"Fix gcmc put atom outside box");
+
   int proc_flag = 0;
   if (coord[0] >= sublo[0] && coord[0] < subhi[0] &&
       coord[1] >= sublo[1] && coord[1] < subhi[1] &&
@@ -1540,6 +1556,8 @@ void FixGCMC::attempt_molecule_translation_full()
       x[i][0] += com_displace[0];
       x[i][1] += com_displace[1];
       x[i][2] += com_displace[2];
+      if (!domain->inside(x[i])) 
+  	error->one(FLERR,"Fix gcmc put atom outside box");
     }
   }
 
@@ -1621,6 +1639,8 @@ void FixGCMC::attempt_molecule_rotation_full()
       x[i][2] += com[2];
       image[i] = imagetmp;
       domain->remap(x[i],image[i]);
+      if (!domain->inside(x[i])) 
+	error->one(FLERR,"Fix gcmc put atom outside box");
       n++;
     }
   }
@@ -1787,6 +1807,8 @@ void FixGCMC::attempt_molecule_insertion_full()
     xtmp[2] += com_coord[2];
     
     domain->remap(xtmp);
+    if (!domain->inside(xtmp)) 
+      error->one(FLERR,"Fix gcmc put atom outside box");
 
     if (xtmp[0] >= sublo[0] && xtmp[0] < subhi[0] &&
         xtmp[1] >= sublo[1] && xtmp[1] < subhi[1] &&
diff --git a/src/domain.cpp b/src/domain.cpp
index da93f50720..134065a506 100644
--- a/src/domain.cpp
+++ b/src/domain.cpp
@@ -583,6 +583,40 @@ void Domain::pbc()
   }
 }
 
+/* ----------------------------------------------------------------------
+   check that point is inside box boundaries, in [lo,hi) sense
+   return 1 if true, 0 if false
+------------------------------------------------------------------------- */
+
+int Domain::inside(double* x)
+{
+  double *lo,*hi,*period;
+  double delta[3];
+
+  if (triclinic == 0) {
+    lo = boxlo;
+    hi = boxhi;
+    period = prd;
+  } else {
+    lo = boxlo_lamda;
+    hi = boxhi_lamda;
+    period = prd_lamda;
+
+    delta[0] = x[0] - boxlo[0];
+    delta[1] = x[1] - boxlo[1];
+    delta[2] = x[2] - boxlo[2];
+
+    x[0] = h_inv[0]*delta[0] + h_inv[5]*delta[1] + h_inv[4]*delta[2];
+    x[1] = h_inv[1]*delta[1] + h_inv[3]*delta[2];
+    x[2] = h_inv[2]*delta[2];
+  }
+
+  if (x[0] < lo[0] || x[0] >= hi[0] ||
+      x[1] < lo[1] || x[1] >= hi[1] ||
+      x[2] < lo[2] || x[2] >= hi[2]) return 0;
+  else return 1;
+}
+
 /* ----------------------------------------------------------------------
    warn if image flags of any bonded atoms are inconsistent
    could be a problem when using replicate or fix rigid
diff --git a/src/domain.h b/src/domain.h
index 12eb9aacef..d6373ecfb1 100644
--- a/src/domain.h
+++ b/src/domain.h
@@ -126,6 +126,7 @@ class Domain : protected Pointers {
   virtual void x2lamda(int);
   virtual void lamda2x(double *, double *);
   virtual void x2lamda(double *, double *);
+  int inside(double *);
   void x2lamda(double *, double *, double *, double *);
   void bbox(double *, double *, double *, double *);
   void box_corners();