diff --git a/modules/cloudsql-instance/README.md b/modules/cloudsql-instance/README.md
index 341c9d00..0cd19684 100644
--- a/modules/cloudsql-instance/README.md
+++ b/modules/cloudsql-instance/README.md
@@ -104,7 +104,8 @@ module "db" {
 | tier | The machine type to use for the instances. | <code title="">string</code> | ✓ |  |
 | *authorized_networks* | Map of NAME=>CIDR_RANGE to allow to connect to the database(s). | <code title="map&#40;string&#41;">map(string)</code> |  | <code title="">null</code> |
 | *availability_type* | Availability type for the primary replica. Either `ZONAL` or `REGIONAL` | <code title="">string</code> |  | <code title="">ZONAL</code> |
-| *backup_configuration* | Backup settings for primary instance. Will be automatically enabled if using MySQL with one or more replicas | <code title="object&#40;&#123;&#10;enabled            &#61; bool&#10;binary_log_enabled &#61; bool&#10;&#125;&#41;">object({...})</code> |  | <code title="&#123;&#10;enabled            &#61; false&#10;binary_log_enabled &#61; false&#10;&#125;">...</code> |
+| *backup_configuration* | Backup settings for primary instance. Will be automatically enabled if using MySQL with one or more replicas | <code title="object&#40;&#123;&#10;enabled            &#61; bool&#10;binary_log_enabled &#61; bool&#10;start_time         &#61; string&#10;location           &#61; string&#10;log_retention_days &#61; number&#10;&#125;&#41;">object({...})</code> |  | <code title="&#123;&#10;enabled            &#61; false&#10;binary_log_enabled &#61; false&#10;start_time         &#61; &#34;23:00&#34;&#10;location           &#61; &#34;EU&#34;&#10;log_retention_days &#61; 7&#10;&#125;">...</code> |
+| *backup_retention_settings* | Backup retention subblock settings. | <code title="object&#40;&#123;&#10;retained_backups &#61; number&#10;retention_unit   &#61; string&#10;&#125;&#41;">object({...})</code> |  | <code title="&#123;&#10;retained_backups &#61; 7&#10;retention_unit   &#61; &#34;COUNT&#34;&#10;&#125;">...</code> |
 | *databases* | Databases to create once the primary instance is created. | <code title="list&#40;string&#41;">list(string)</code> |  | <code title="">null</code> |
 | *deletion_protection* | Allow terraform to delete instances. | <code title="">bool</code> |  | <code title="">false</code> |
 | *disk_size* | Disk size in GB. Set to null to enable autoresize. | <code title="">number</code> |  | <code title="">null</code> |