diff --git a/doc/USER_GUIDE.md b/doc/USER_GUIDE.md
index f96c046ea..b0a704127 100644
--- a/doc/USER_GUIDE.md
+++ b/doc/USER_GUIDE.md
@@ -58,7 +58,7 @@ Users have the following options for specifying their own values:
 | `source_ami_owners` | ```137112412989``` |  |
 | `ssh_interface` | `""` |  |
 | `ssh_username` | ```ec2-user``` |  |
-| `ssm_agent_version` | ```latest``` |  |
+| `ssm_agent_version` | `""` | Version of the SSM agent to install from the S3 bucket provided by the SSM agent project, such as ```latest```. If empty, the latest version of the SSM agent available in the Amazon Linux core repositories will be installed. |
 | `subnet_id` | `""` |  |
 | `temporary_security_group_source_cidrs` | `""` |  |
 | `volume_type` | ```gp2``` |  |
diff --git a/eks-worker-al2-variables.json b/eks-worker-al2-variables.json
index 43b60748c..0e02f145c 100644
--- a/eks-worker-al2-variables.json
+++ b/eks-worker-al2-variables.json
@@ -31,7 +31,7 @@
     "source_ami_owners": "137112412989",
     "ssh_interface": "",
     "ssh_username": "ec2-user",
-    "ssm_agent_version": "latest",
+    "ssm_agent_version": "",
     "subnet_id": "",
     "temporary_security_group_source_cidrs": "",
     "volume_type": "gp2",
diff --git a/scripts/install-worker.sh b/scripts/install-worker.sh
index fe319b628..7cee78cd3 100644
--- a/scripts/install-worker.sh
+++ b/scripts/install-worker.sh
@@ -32,7 +32,6 @@ validate_env_set PULL_CNI_FROM_GITHUB
 validate_env_set PAUSE_CONTAINER_VERSION
 validate_env_set CACHE_CONTAINER_IMAGES
 validate_env_set WORKING_DIR
-validate_env_set SSM_AGENT_VERSION
 
 ################################################################################
 ### Machine Architecture #######################################################
@@ -512,10 +511,11 @@ fi
 if yum list installed | grep amazon-ssm-agent; then
   echo "amazon-ssm-agent already present - skipping install"
 else
-  echo "Installing amazon-ssm-agent"
-  if ! [[ ${ISOLATED_REGIONS} =~ $BINARY_BUCKET_REGION ]]; then
+  if ! [[ -z "${SSM_AGENT_VERSION}" ]]; then
+    echo "Installing amazon-ssm-agent@${SSM_AGENT_VERSION} from S3"
     sudo yum install -y https://s3.${BINARY_BUCKET_REGION}.${S3_DOMAIN}/amazon-ssm-${BINARY_BUCKET_REGION}/${SSM_AGENT_VERSION}/linux_${ARCH}/amazon-ssm-agent.rpm
   else
+    echo "Installing amazon-ssm-agent from AL core repository"
     sudo yum install -y amazon-ssm-agent
   fi
 fi