diff --git a/moto/ssm/utils.py b/moto/ssm/utils.py
index 35ae251dd..3f3762d1c 100644
--- a/moto/ssm/utils.py
+++ b/moto/ssm/utils.py
@@ -1,4 +1,9 @@
+ACCOUNT_ID = "1234567890"
+
+
 def parameter_arn(region, parameter_name):
     if parameter_name[0] == "/":
         parameter_name = parameter_name[1:]
-    return "arn:aws:ssm:{0}:1234567890:parameter/{1}".format(region, parameter_name)
+    return "arn:aws:ssm:{0}:{1}:parameter/{2}".format(
+        region, ACCOUNT_ID, parameter_name
+    )