diff --git a/moto/elasticbeanstalk/models.py b/moto/elasticbeanstalk/models.py
index 3767846c..13650bb2 100644
--- a/moto/elasticbeanstalk/models.py
+++ b/moto/elasticbeanstalk/models.py
@@ -2,8 +2,9 @@ import weakref
 
 from boto3 import Session
 
-from moto.core import BaseBackend, BaseModel
+from moto.core import BaseBackend, BaseModel, ACCOUNT_ID
 from .exceptions import InvalidParameterValueError, ResourceNotFoundException
+from .utils import make_arn
 
 
 class FakeEnvironment(BaseModel):
@@ -23,15 +24,8 @@ class FakeEnvironment(BaseModel):
 
     @property
     def environment_arn(self):
-        return (
-            "arn:aws:elasticbeanstalk:{region}:{account_id}:"
-            "environment/{application_name}/{environment_name}".format(
-                region=self.region,
-                account_id="123456789012",
-                application_name=self.application_name,
-                environment_name=self.environment_name,
-            )
-        )
+        resource_path = "%s/%s" % (self.application_name, self.environment_name)
+        return make_arn(self.region, ACCOUNT_ID, "environment", resource_path)
 
     @property
     def platform_arn(self):
@@ -68,6 +62,10 @@ class FakeApplication(BaseModel):
     def region(self):
         return self.backend.region
 
+    @property
+    def arn(self):
+        return make_arn(self.region, ACCOUNT_ID, "application", self.application_name)
+
 
 class EBBackend(BaseBackend):
     def __init__(self, region):
diff --git a/moto/elasticbeanstalk/responses.py b/moto/elasticbeanstalk/responses.py
index 9b6d1099..9759f71c 100644
--- a/moto/elasticbeanstalk/responses.py
+++ b/moto/elasticbeanstalk/responses.py
@@ -91,7 +91,7 @@ EB_CREATE_APPLICATION = """
           </MaxCountRule>
         </VersionLifecycleConfig>
       </ResourceLifecycleConfig>
-      <ApplicationArn>arn:aws:elasticbeanstalk:{{ region_name }}:111122223333:application/{{ application.application_name }}</ApplicationArn>
+      <ApplicationArn>{{ application.arn }}</ApplicationArn>
       <ApplicationName>{{ application.application_name }}</ApplicationName>
       <DateUpdated>2019-09-03T13:08:29.049Z</DateUpdated>
     </Application>
@@ -125,7 +125,7 @@ EB_DESCRIBE_APPLICATIONS = """
             </MaxCountRule>
           </VersionLifecycleConfig>
         </ResourceLifecycleConfig>
-        <ApplicationArn>arn:aws:elasticbeanstalk:{{ region_name }}:111122223333:application/{{ application.application_name }}</ApplicationArn>
+        <ApplicationArn>{{ application.arn }}</ApplicationArn>
         <ApplicationName>{{ application.application_name }}</ApplicationName>
         <DateUpdated>2019-09-03T13:08:29.049Z</DateUpdated>
       </member>
diff --git a/moto/elasticbeanstalk/utils.py b/moto/elasticbeanstalk/utils.py
new file mode 100644
index 00000000..e3e22a11
--- /dev/null
+++ b/moto/elasticbeanstalk/utils.py
@@ -0,0 +1,11 @@
+def make_arn(region, account_id, resource_type, resource_path):
+    arn_template = (
+        "arn:aws:elasticbeanstalk:{region}:{account_id}:{resource_type}/{resource_path}"
+    )
+    arn = arn_template.format(
+        region=region,
+        account_id=account_id,
+        resource_type=resource_type,
+        resource_path=resource_path,
+    )
+    return arn
diff --git a/tests/test_elasticbeanstalk/test_eb.py b/tests/test_elasticbeanstalk/test_eb.py
index 15b8f86e..410f1862 100644
--- a/tests/test_elasticbeanstalk/test_eb.py
+++ b/tests/test_elasticbeanstalk/test_eb.py
@@ -42,6 +42,7 @@ def test_create_environment():
     app = conn.create_application(ApplicationName="myapp",)
     env = conn.create_environment(ApplicationName="myapp", EnvironmentName="myenv",)
     env["EnvironmentName"].should.equal("myenv")
+    env["EnvironmentArn"].should.contain("myapp/myenv")
 
 
 @mock_elasticbeanstalk
@@ -58,6 +59,7 @@ def test_describe_environments():
     len(envs).should.equal(1)
     envs[0]["ApplicationName"].should.equal("myapp")
     envs[0]["EnvironmentName"].should.equal("myenv")
+    envs[0]["EnvironmentArn"].should.contain("myapp/myenv")
 
 
 def tags_dict_to_list(tag_dict):