diff --git a/_sub/database/postgres/main.tf b/_sub/database/postgres/main.tf
index 965354fba..05f1aa9e9 100644
--- a/_sub/database/postgres/main.tf
+++ b/_sub/database/postgres/main.tf
@@ -61,14 +61,15 @@ resource "aws_db_instance" "postgres" {
   final_snapshot_identifier = "${var.application}-postgres-final-${var.environment}"
 
   # configurable
-  storage_type        = var.db_storage_type
-  instance_class      = var.db_instance_class
-  allocated_storage   = var.db_allocated_storage
-  port                = var.db_port
-  name                = var.db_name
-  username            = var.db_master_username
-  password            = var.db_master_password
-  skip_final_snapshot = var.skip_final_snapshot
+  storage_type                  = var.db_storage_type
+  instance_class                = var.db_instance_class
+  allocated_storage             = var.db_allocated_storage
+  port                          = var.db_port
+  name                          = var.db_name
+  username                      = var.db_master_username
+  password                      = var.db_master_password
+  skip_final_snapshot           = var.skip_final_snapshot
+  allow_major_version_upgrade   = var.allow_major_version_upgrade
 
   timeouts {
     create = "2h"
diff --git a/_sub/database/postgres/vars.tf b/_sub/database/postgres/vars.tf
index c57bc9afd..7d3e077a3 100644
--- a/_sub/database/postgres/vars.tf
+++ b/_sub/database/postgres/vars.tf
@@ -49,3 +49,9 @@ variable "engine_version" {
   description = "RDS engine version (expects major version)"
   default     = null
 }
+
+variable "allow_major_version_upgrade" {
+  type        = bool
+  description = "Define if major version upgrades to the Postgres engine are allowed"
+  default     = true
+}
diff --git a/database/postgres/README.md b/database/postgres/README.md
index cb467673f..3004f7e2c 100644
--- a/database/postgres/README.md
+++ b/database/postgres/README.md
@@ -15,3 +15,4 @@ The connection strings, passwords etc can be found in parameter store in the sam
 - engine_version = 10 (Must be major version. Cannot be downgraded. Optional, but defaults to 10)
 - db_instance_class - "db.t3.nano" RDS (database instance class. Optional, but defaults to "db.t2.micro")
 - db_allocated_storage - 10 (The amount of space, in GB, to allocate for the database. Optional, but defaults to 20)
+- allow_major_version_upgrade = true (Define if major version upgrades to the Postgres engine are allowed. Optional, but defaults to true)
\ No newline at end of file
diff --git a/database/postgres/main.tf b/database/postgres/main.tf
index 69c0d5d52..16e643613 100644
--- a/database/postgres/main.tf
+++ b/database/postgres/main.tf
@@ -15,17 +15,18 @@ provider "aws" {
 # --------------------------------------------------
 
 module "postgres" {
-  source              = "../../_sub/database/postgres"
-  application         = var.application
-  environment         = var.environment
-  db_name             = var.db_name
-  db_master_username  = var.db_master_username
-  db_master_password  = var.db_master_password
-  db_port             = var.db_port
-  skip_final_snapshot = var.skip_final_snapshot
-  engine_version      = var.engine_version
-  db_instance_class   = var.db_instance_class
-  db_allocated_storage   = var.db_allocated_storage
+  source                        = "../../_sub/database/postgres"
+  application                   = var.application
+  environment                   = var.environment
+  db_name                       = var.db_name
+  db_master_username            = var.db_master_username
+  db_master_password            = var.db_master_password
+  db_port                       = var.db_port
+  skip_final_snapshot           = var.skip_final_snapshot
+  engine_version                = var.engine_version
+  db_instance_class             = var.db_instance_class
+  db_allocated_storage          = var.db_allocated_storage
+  allow_major_version_upgrade   = var.allow_major_version_upgrade
 }
 
 module "param_store_pghost" {
diff --git a/database/postgres/vars.tf b/database/postgres/vars.tf
index 3528236c9..96b6dea3b 100644
--- a/database/postgres/vars.tf
+++ b/database/postgres/vars.tf
@@ -49,3 +49,9 @@ variable "db_allocated_storage" {
   description = "The amount of space, in GB, to allocate for the database"
   default     = 20
 }
+
+variable "allow_major_version_upgrade" {
+  type        = bool
+  description = "Define if major version upgrades to the Postgres engine are allowed"
+  default     = true
+}