diff --git a/tests/aws/test_libeb.py b/tests/aws/test_libeb.py
index 1aea660..3a28513 100644
--- a/tests/aws/test_libeb.py
+++ b/tests/aws/test_libeb.py
@@ -13,7 +13,7 @@ class LibEBUnitTests(AWSTestCase):
 
     def setUp(self):
         super(LibEBUnitTests, self).setUp()
-        mock_eb_client = boto3.client('events')
+        mock_eb_client = boto3.client('events', region_name='us-east-1')
         self.stubber = Stubber(mock_eb_client)
         self.stubber.activate()
         when(aws).eb_client(...).thenReturn(mock_eb_client)
diff --git a/tests/aws/test_libsm.py b/tests/aws/test_libsm.py
index 78ea23b..5e7ea1d 100644
--- a/tests/aws/test_libsm.py
+++ b/tests/aws/test_libsm.py
@@ -16,7 +16,7 @@ class LibSmUnitTests(TestCase):
 
     def setUp(self):
         from libumccr.aws import libsm
-        mock_sm_client = boto3.client('secretsmanager')
+        mock_sm_client = boto3.client('secretsmanager', region_name='us-east-1')
         stubber = Stubber(mock_sm_client)
         stubber.add_response('get_secret_value', {
             'SecretString': 'HealTheWorld',  # pragma: allowlist secret
diff --git a/tests/aws/test_libssm.py b/tests/aws/test_libssm.py
index 707c785..1e6a5df 100644
--- a/tests/aws/test_libssm.py
+++ b/tests/aws/test_libssm.py
@@ -16,7 +16,7 @@ class LibSsmUnitTests(TestCase):
 
     def setUp(self):
         from libumccr.aws import libssm
-        mock_ssm_client = boto3.client('ssm')
+        mock_ssm_client = boto3.client('ssm', region_name='us-east-1')
         stubber = Stubber(mock_ssm_client)
         stubber.add_response('get_parameter', {'Parameter': {'Value': 'Sello'}})
         stubber.activate()