diff --git a/pySim-prog.py b/pySim-prog.py
index 7c644b79..028db55f 100755
--- a/pySim-prog.py
+++ b/pySim-prog.py
@@ -357,8 +357,8 @@ def gen_parameters(opts):
     # ICCID (19 digits, E.118), though some phase1 vendors use 20 :(
     if opts.iccid is not None:
         iccid = opts.iccid
-        if not _isnum(iccid, 19) and not _isnum(iccid, 20):
-            raise ValueError('ICCID must be 19 or 20 digits !')
+        if not _isnum(iccid, 18) and not _isnum(iccid, 19) and not _isnum(iccid, 20):
+            raise ValueError('ICCID must be 18, 19 or 20 digits !')
 
     else:
         if opts.num is None: