diff --git a/botocore/data/ecs/2014-11-13/waiters-2.json b/botocore/data/ecs/2014-11-13/waiters-2.json
index 8a0b19d8e3..1388666be2 100644
--- a/botocore/data/ecs/2014-11-13/waiters-2.json
+++ b/botocore/data/ecs/2014-11-13/waiters-2.json
@@ -66,7 +66,7 @@
           "expected": true,
           "matcher": "path",
           "state": "success",
-          "argument": "length(services[?!(length(deployments) == `1` && runningCount == desiredCount)]) == `0`"
+          "argument": "length(services[?!(length(deployments || `[]`) == `1` && runningCount == desiredCount)]) == `0`"
         }
       ]
     },
diff --git a/tests/functional/test_ecs.py b/tests/functional/test_ecs.py
new file mode 100644
index 0000000000..0535ebdf65
--- /dev/null
+++ b/tests/functional/test_ecs.py
@@ -0,0 +1,136 @@
+# Copyright 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"). You
+# may not use this file except in compliance with the License. A copy of
+# the License is located at
+#
+# http://aws.amazon.com/apache2.0/
+#
+# or in the "license" file accompanying this file. This file is
+# distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF
+# ANY KIND, either express or implied. See the License for the specific
+# language governing permissions and limitations under the License.
+import botocore.session
+from botocore.stub import Stubber
+
+
+def _create_ecs_client():
+    session = botocore.session.get_session()
+    return session.create_client('ecs', region_name='us-east-1')
+
+
+def test_services_stable_waiter_with_missing_deployments():
+    """ServicesStable waiter should not raise when deployments key is absent.
+
+    When a service is deployed using CodeDeploy Blue/Green, the
+    DescribeServices response may not include a ``deployments`` field.
+    The waiter must handle this gracefully instead of raising a
+    JMESPathTypeError.
+    """
+    client = _create_ecs_client()
+    stubber = Stubber(client)
+
+    # First response: service without deployments key — the waiter should
+    # treat this as "not yet stable" and retry rather than crashing.
+    response_missing_deployments = {
+        'services': [
+            {
+                'serviceName': 'my-service',
+                'clusterArn': 'arn:aws:ecs:us-east-1:123456789012:cluster/my-cluster',
+                'serviceArn': 'arn:aws:ecs:us-east-1:123456789012:service/my-cluster/my-service',
+                'status': 'ACTIVE',
+                'desiredCount': 1,
+                'runningCount': 1,
+                'launchType': 'FARGATE',
+            }
+        ],
+        'failures': [],
+    }
+
+    # Second response: service with a single deployment and matching counts —
+    # this should satisfy the waiter's success condition.
+    response_stable = {
+        'services': [
+            {
+                'serviceName': 'my-service',
+                'clusterArn': 'arn:aws:ecs:us-east-1:123456789012:cluster/my-cluster',
+                'serviceArn': 'arn:aws:ecs:us-east-1:123456789012:service/my-cluster/my-service',
+                'status': 'ACTIVE',
+                'desiredCount': 1,
+                'runningCount': 1,
+                'deployments': [
+                    {
+                        'id': 'ecs-svc/1234567890123456789',
+                        'status': 'PRIMARY',
+                        'desiredCount': 1,
+                        'runningCount': 1,
+                    }
+                ],
+                'launchType': 'FARGATE',
+            }
+        ],
+        'failures': [],
+    }
+
+    expected_params = {
+        'cluster': 'my-cluster',
+        'services': ['my-service'],
+    }
+
+    stubber.add_response('describe_services', response_missing_deployments, expected_params)
+    stubber.add_response('describe_services', response_stable, expected_params)
+
+    waiter = client.get_waiter('services_stable')
+    waiter.config.delay = 0  # No delay for tests
+
+    with stubber:
+        # This should not raise a JMESPathTypeError
+        waiter.wait(
+            cluster='my-cluster',
+            services=['my-service'],
+        )
+
+
+def test_services_stable_waiter_with_deployments_present():
+    """ServicesStable waiter succeeds when deployments is present and stable."""
+    client = _create_ecs_client()
+    stubber = Stubber(client)
+
+    response_stable = {
+        'services': [
+            {
+                'serviceName': 'my-service',
+                'clusterArn': 'arn:aws:ecs:us-east-1:123456789012:cluster/my-cluster',
+                'serviceArn': 'arn:aws:ecs:us-east-1:123456789012:service/my-cluster/my-service',
+                'status': 'ACTIVE',
+                'desiredCount': 2,
+                'runningCount': 2,
+                'deployments': [
+                    {
+                        'id': 'ecs-svc/1234567890123456789',
+                        'status': 'PRIMARY',
+                        'desiredCount': 2,
+                        'runningCount': 2,
+                    }
+                ],
+                'launchType': 'FARGATE',
+            }
+        ],
+        'failures': [],
+    }
+
+    expected_params = {
+        'cluster': 'my-cluster',
+        'services': ['my-service'],
+    }
+
+    stubber.add_response('describe_services', response_stable, expected_params)
+
+    waiter = client.get_waiter('services_stable')
+    waiter.config.delay = 0
+
+    with stubber:
+        waiter.wait(
+            cluster='my-cluster',
+            services=['my-service'],
+        )