diff --git a/src/MO_Basis/swap_mos.irp.f b/src/MO_Basis/swap_mos.irp.f
new file mode 100644
index 00000000..df0dc64d
--- /dev/null
+++ b/src/MO_Basis/swap_mos.irp.f
@@ -0,0 +1,14 @@
+program swap_mos
+  implicit none
+  integer :: i,j, i1, i2
+  double precision :: x
+  print *,  'MOs to swap?'
+  read(*,*) i1, i2
+  do i=1,ao_num_align
+    x = mo_coef(i,i1)
+    mo_coef(i,i1) = mo_coef(i,i2)
+    mo_coef(i,i2) = x
+  enddo
+  call save_mos
+
+end