diff --git a/README.md b/README.md
index e006e43..91bbdda 100644
--- a/README.md
+++ b/README.md
@@ -274,6 +274,7 @@ This project creates and manages resources within an AWS account for infrastruct
 | [aws_security_group.infrastructure_ecs_cluster_service_alb](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group) | resource |
 | [aws_security_group.infrastructure_elasticache](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group) | resource |
 | [aws_security_group.infrastructure_rds](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group) | resource |
+| [aws_security_group_rule.infrastructure_ecs_cluster_container_instances_custom](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group_rule) | resource |
 | [aws_security_group_rule.infrastructure_ecs_cluster_container_instances_egress_dns_tcp](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group_rule) | resource |
 | [aws_security_group_rule.infrastructure_ecs_cluster_container_instances_egress_dns_udp](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group_rule) | resource |
 | [aws_security_group_rule.infrastructure_ecs_cluster_container_instances_egress_https_tcp](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group_rule) | resource |
@@ -340,6 +341,7 @@ This project creates and manages resources within an AWS account for infrastruct
 | <a name="input_infrastructure_ecs_cluster_autoscaling_time_based_custom"></a> [infrastructure\_ecs\_cluster\_autoscaling\_time\_based\_custom](#input\_infrastructure\_ecs\_cluster\_autoscaling\_time\_based\_custom) | List of objects with min/max sizes and cron expressions to scale the ECS cluster. Min size will be used as desired. | <pre>list(<br>    object({<br>      cron = string<br>      min  = number<br>      max  = number<br>    })<br>  )</pre> | n/a | yes |
 | <a name="input_infrastructure_ecs_cluster_autoscaling_time_based_max"></a> [infrastructure\_ecs\_cluster\_autoscaling\_time\_based\_max](#input\_infrastructure\_ecs\_cluster\_autoscaling\_time\_based\_max) | List of cron expressions to scale the ECS cluster to the configured max size | `list(string)` | n/a | yes |
 | <a name="input_infrastructure_ecs_cluster_autoscaling_time_based_min"></a> [infrastructure\_ecs\_cluster\_autoscaling\_time\_based\_min](#input\_infrastructure\_ecs\_cluster\_autoscaling\_time\_based\_min) | List of cron expressions to scale the ECS cluster to the configured min size | `list(string)` | n/a | yes |
+| <a name="input_infrastructure_ecs_cluster_custom_security_group_rules"></a> [infrastructure\_ecs\_cluster\_custom\_security\_group\_rules](#input\_infrastructure\_ecs\_cluster\_custom\_security\_group\_rules) | Map of custom security group rules to add to the ECS Cluster security group (eg. { rule-name = {type = "egress", ... }  }) | <pre>map(object({<br>    description              = string<br>    type                     = string<br>    from_port                = number<br>    to_port                  = number<br>    protocol                 = string<br>    source_security_group_id = optional(string, "")<br>    cidr_blocks              = optional(list(string), [])<br>  }))</pre> | n/a | yes |
 | <a name="input_infrastructure_ecs_cluster_draining_lambda_enabled"></a> [infrastructure\_ecs\_cluster\_draining\_lambda\_enabled](#input\_infrastructure\_ecs\_cluster\_draining\_lambda\_enabled) | Enable the Lambda which ensures all containers have drained before terminating ECS cluster instances | `bool` | n/a | yes |
 | <a name="input_infrastructure_ecs_cluster_draining_lambda_log_retention"></a> [infrastructure\_ecs\_cluster\_draining\_lambda\_log\_retention](#input\_infrastructure\_ecs\_cluster\_draining\_lambda\_log\_retention) | Log retention for the ECS cluster draining Lambda | `number` | n/a | yes |
 | <a name="input_infrastructure_ecs_cluster_ebs_docker_storage_volume_size"></a> [infrastructure\_ecs\_cluster\_ebs\_docker\_storage\_volume\_size](#input\_infrastructure\_ecs\_cluster\_ebs\_docker\_storage\_volume\_size) | Size of EBS volume for Docker storage on the infrastructure ECS instances | `number` | n/a | yes |
diff --git a/ecs-cluster-infrastructure-security-group.tf b/ecs-cluster-infrastructure-security-group.tf
index 9976393..eb60ea5 100644
--- a/ecs-cluster-infrastructure-security-group.tf
+++ b/ecs-cluster-infrastructure-security-group.tf
@@ -113,3 +113,16 @@ resource "aws_security_group_rule" "infrastructure_ecs_cluster_container_instanc
   source_security_group_id = aws_security_group.infrastructure_rds[each.key].id
   security_group_id        = aws_security_group.infrastructure_ecs_cluster_container_instances[0].id
 }
+
+resource "aws_security_group_rule" "infrastructure_ecs_cluster_container_instances_custom" {
+  for_each = local.enable_infrastructure_ecs_cluster ? local.infrastructure_ecs_cluster_custom_security_group_rules : {}
+
+  description              = each.value["description"]
+  type                     = each.value["type"]
+  from_port                = each.value["from_port"]
+  to_port                  = each.value["to_port"]
+  protocol                 = each.value["protocol"]
+  source_security_group_id = each.value["source_security_group_id"] != "" ? each.value["source_security_group_id"] : null
+  cidr_blocks              = length(each.value["cidr_blocks"]) > 0 ? each.value["cidr_blocks"] : null
+  security_group_id        = aws_security_group.infrastructure_ecs_cluster_container_instances[0].id
+}
diff --git a/locals.tf b/locals.tf
index a34250f..77dedc7 100644
--- a/locals.tf
+++ b/locals.tf
@@ -118,6 +118,7 @@ locals {
   infrastructure_ecs_cluster_ebs_docker_storage_volume_size        = var.infrastructure_ecs_cluster_ebs_docker_storage_volume_size
   infrastructure_ecs_cluster_ebs_docker_storage_volume_type        = var.infrastructure_ecs_cluster_ebs_docker_storage_volume_type
   infrastructure_ecs_cluster_publicly_avaialble                    = var.infrastructure_ecs_cluster_publicly_avaialble && local.infrastructure_vpc_network_enable_public
+  infrastructure_ecs_cluster_custom_security_group_rules           = var.infrastructure_ecs_cluster_custom_security_group_rules
   infrastructure_ecs_cluster_instance_type                         = var.infrastructure_ecs_cluster_instance_type
   infrastructure_ecs_cluster_termination_timeout                   = var.infrastructure_ecs_cluster_termination_timeout
   infrastructure_ecs_cluster_draining_lambda_enabled               = var.infrastructure_ecs_cluster_draining_lambda_enabled && local.enable_infrastructure_ecs_cluster
diff --git a/variables.tf b/variables.tf
index 1e2876e..d3e250d 100644
--- a/variables.tf
+++ b/variables.tf
@@ -244,6 +244,19 @@ variable "infrastructure_ecs_cluster_publicly_avaialble" {
   type        = bool
 }
 
+variable "infrastructure_ecs_cluster_custom_security_group_rules" {
+  description = "Map of custom security group rules to add to the ECS Cluster security group (eg. { rule-name = {type = \"egress\", ... }  })"
+  type = map(object({
+    description              = string
+    type                     = string
+    from_port                = number
+    to_port                  = number
+    protocol                 = string
+    source_security_group_id = optional(string, "")
+    cidr_blocks              = optional(list(string), [])
+  }))
+}
+
 variable "infrastructure_ecs_cluster_instance_type" {
   description = "The instance type for EC2 instances launched in the ECS cluster"
   type        = string