diff --git a/.changelog/28434.txt b/.changelog/28434.txt
new file mode 100644
index 00000000000..7c9c4a3ad92
--- /dev/null
+++ b/.changelog/28434.txt
@@ -0,0 +1,7 @@
+```release-note:enhancement
+resource/aws_db_instance: Add `listener_endpoint` attribute
+```
+
+```release-note:enhancement
+resource/aws_db_instance: Add plan time validations for `backup_retention_period`, `monitoring_interval`, and `monitoring_role_arn`
+```
\ No newline at end of file
diff --git a/internal/service/rds/instance.go b/internal/service/rds/instance.go
index dff77c99a67..c62ece13b48 100644
--- a/internal/service/rds/instance.go
+++ b/internal/service/rds/instance.go
@@ -121,9 +121,10 @@ func ResourceInstance() *schema.Resource {
 				ForceNew: true,
 			},
 			"backup_retention_period": {
-				Type:     schema.TypeInt,
-				Optional: true,
-				Computed: true,
+				Type:         schema.TypeInt,
+				Optional:     true,
+				Computed:     true,
+				ValidateFunc: validation.IntBetween(0, 35),
 			},
 			"backup_window": {
 				Type:         schema.TypeString,
@@ -294,6 +295,26 @@ func ResourceInstance() *schema.Resource {
 				Optional: true,
 				Computed: true,
 			},
+			"listener_endpoint": {
+				Type:     schema.TypeList,
+				Computed: true,
+				Elem: &schema.Resource{
+					Schema: map[string]*schema.Schema{
+						"address": {
+							Type:     schema.TypeString,
+							Computed: true,
+						},
+						"hosted_zone_id": {
+							Type:     schema.TypeString,
+							Computed: true,
+						},
+						"port": {
+							Type:     schema.TypeInt,
+							Computed: true,
+						},
+					},
+				},
+			},
 			"maintenance_window": {
 				Type:     schema.TypeString,
 				Optional: true,
@@ -318,14 +339,16 @@ func ResourceInstance() *schema.Resource {
 				},
 			},
 			"monitoring_interval": {
-				Type:     schema.TypeInt,
-				Optional: true,
-				Default:  0,
+				Type:         schema.TypeInt,
+				Optional:     true,
+				Default:      0,
+				ValidateFunc: validation.IntInSlice([]int{0, 1, 5, 10, 15, 30, 60}),
 			},
 			"monitoring_role_arn": {
-				Type:     schema.TypeString,
-				Optional: true,
-				Computed: true,
+				Type:         schema.TypeString,
+				Optional:     true,
+				Computed:     true,
+				ValidateFunc: verify.ValidARN,
 			},
 			"multi_az": {
 				Type:     schema.TypeBool,
@@ -1644,6 +1667,14 @@ func resourceInstanceRead(ctx context.Context, d *schema.ResourceData, meta inte
 		d.Set("port", v.Endpoint.Port)
 	}
 
+	if v.ListenerEndpoint != nil {
+		if err := d.Set("listener_endpoint", []interface{}{flattenEndpoint(v.ListenerEndpoint)}); err != nil {
+			return sdkdiag.AppendErrorf(diags, "setting listener_endpoint: %s", err)
+		}
+	} else {
+		d.Set("listener_endpoint", nil)
+	}
+
 	dbSetResourceDataEngineVersionFromInstance(d, v)
 
 	tags, err := ListTags(ctx, conn, arn)
@@ -2585,3 +2616,25 @@ func dbInstanceValidBlueGreenEngines() []string {
 		InstanceEngineMySQL,
 	}
 }
+
+func flattenEndpoint(apiObject *rds.Endpoint) map[string]interface{} {
+	if apiObject == nil {
+		return nil
+	}
+
+	tfMap := map[string]interface{}{}
+
+	if v := apiObject.Address; v != nil {
+		tfMap["address"] = aws.StringValue(v)
+	}
+
+	if v := apiObject.HostedZoneId; v != nil {
+		tfMap["hosted_zone_id"] = aws.StringValue(v)
+	}
+
+	if v := apiObject.Port; v != nil {
+		tfMap["port"] = aws.Int64Value(v)
+	}
+
+	return tfMap
+}
diff --git a/internal/service/rds/instance_test.go b/internal/service/rds/instance_test.go
index 202e22a64ff..feddd6caddd 100644
--- a/internal/service/rds/instance_test.go
+++ b/internal/service/rds/instance_test.go
@@ -65,6 +65,7 @@ func TestAccRDSInstance_basic(t *testing.T) {
 					resource.TestCheckResourceAttrPair(resourceName, "instance_class", "data.aws_rds_orderable_db_instance.test", "instance_class"),
 					resource.TestCheckResourceAttr(resourceName, "iops", "0"),
 					resource.TestCheckResourceAttr(resourceName, "license_model", "general-public-license"),
+					resource.TestCheckResourceAttr(resourceName, "listener_endpoint.#", "0"),
 					resource.TestCheckResourceAttrSet(resourceName, "maintenance_window"),
 					resource.TestCheckResourceAttr(resourceName, "max_allocated_storage", "0"),
 					resource.TestCheckResourceAttr(resourceName, "name", "test"),
@@ -2827,6 +2828,7 @@ func TestAccRDSInstance_SnapshotIdentifier_multiAZSQLServer(t *testing.T) {
 					testAccCheckInstanceExists(ctx, sourceDbResourceName, &sourceDbInstance),
 					testAccCheckDBSnapshotExists(ctx, snapshotResourceName, &dbSnapshot),
 					testAccCheckInstanceExists(ctx, resourceName, &dbInstance),
+					resource.TestCheckResourceAttr(resourceName, "listener_endpoint.#", "1"),
 					resource.TestCheckResourceAttr(resourceName, "multi_az", "true"),
 				),
 			},
diff --git a/website/docs/r/db_instance.html.markdown b/website/docs/r/db_instance.html.markdown
index 1bf84969602..f651034e53a 100644
--- a/website/docs/r/db_instance.html.markdown
+++ b/website/docs/r/db_instance.html.markdown
@@ -309,6 +309,7 @@ in a Route 53 Alias record).
 * `id` - The RDS instance ID.
 * `instance_class`- The RDS instance class.
 * `latest_restorable_time` - The latest time, in UTC [RFC3339 format](https://tools.ietf.org/html/rfc3339#section-5.8), to which a database can be restored with point-in-time restore.
+* `listener_endpoint` - Specifies the listener connection endpoint for SQL Server Always On. See [endpoint](#endpoint) below.
 * `maintenance_window` - The instance maintenance window.
 * `multi_az` - If the RDS instance is multi AZ enabled.
 * `name` - The database name.
@@ -323,6 +324,12 @@ On Oracle and Microsoft SQL instances the following is exported additionally:
 
 * `character_set_name` - The character set (collation) used on Oracle and Microsoft SQL instances.
 
+### Endpoint
+
+* `address` - Specifies the DNS address of the DB instance.
+* `hosted_zone_id` - Specifies the ID that Amazon Route 53 assigns when you create a hosted zone.
+* `port` - Specifies the port that the database engine is listening on.
+
 ## Timeouts
 
 [Configuration options](https://developer.hashicorp.com/terraform/language/resources/syntax#operation-timeouts):