diff --git a/modules/unreal/horde/examples/complete/dns.tf b/modules/unreal/horde/examples/complete/dns.tf
index e2114f5..4400c89 100644
--- a/modules/unreal/horde/examples/complete/dns.tf
+++ b/modules/unreal/horde/examples/complete/dns.tf
@@ -45,7 +45,7 @@ resource "aws_acm_certificate" "unreal_horde" {
   validation_method = "DNS"
 
   tags = {
-    Environment = "dev"
+    environment = "dev"
   }
 
   lifecycle {
diff --git a/modules/unreal/horde/local.tf b/modules/unreal/horde/local.tf
index 759348f..a0bedb2 100644
--- a/modules/unreal/horde/local.tf
+++ b/modules/unreal/horde/local.tf
@@ -11,7 +11,7 @@ locals {
   image       = "ghcr.io/epicgames/horde-server:latest-bundled"
   name_prefix = "${var.project_prefix}-${var.name}"
   tags = merge(var.tags, {
-    "ENVIRONMENT" = var.environment
+    "environment" = var.environment
   })
 
   elasticache_redis_port                 = 6379
diff --git a/samples/horde-perforce/dns.tf b/samples/horde-perforce/dns.tf
index a97caf7..f8ed1a7 100644
--- a/samples/horde-perforce/dns.tf
+++ b/samples/horde-perforce/dns.tf
@@ -128,7 +128,7 @@ resource "aws_acm_certificate" "unreal_engine_horde" {
   validation_method = "DNS"
 
   tags = {
-    Environment = "dev"
+    environment = "dev"
   }
 
   lifecycle {
@@ -171,7 +171,7 @@ resource "aws_acm_certificate" "helix" {
   validation_method = "DNS"
 
   tags = {
-    Environment = "dev"
+    environment = "dev"
   }
 
   lifecycle {