diff --git a/azurerm/resource_arm_function_app.go b/azurerm/resource_arm_function_app.go
index 7c6095713e89..4d4b6aad45d2 100644
--- a/azurerm/resource_arm_function_app.go
+++ b/azurerm/resource_arm_function_app.go
@@ -228,11 +228,12 @@ func resourceArmFunctionApp() *schema.Resource {
 						"min_tls_version": {
 							Type:     schema.TypeString,
 							Optional: true,
+							Computed: true,
 							ValidateFunc: validation.StringInSlice([]string{
+								string(web.OneFullStopZero),
 								string(web.OneFullStopOne),
 								string(web.OneFullStopTwo),
-								string(web.OneFullStopZero),
-							}, true),
+							}, false),
 						},
 						"cors": azure.SchemaWebCorsSettings(),
 					},
diff --git a/website/docs/r/function_app.html.markdown b/website/docs/r/function_app.html.markdown
index f6168b77de5e..26c6beb606d3 100644
--- a/website/docs/r/function_app.html.markdown
+++ b/website/docs/r/function_app.html.markdown
@@ -149,7 +149,7 @@ The following arguments are supported:
 
 * `http2_enabled` - (Optional) Specifies whether or not the http2 protocol should be enabled. Defaults to `false`.
 
-* `min_tls_version` - (Optional) The minimum supported TLS version. Possible values are `1.0`, `1.1`, and `1.2`.
+* `min_tls_version` - (Optional) The minimum supported TLS version for the function app. Possible values are `1.0`, `1.1`, and `1.2`. Defaults to `1.2` for new function apps.
 
 * `cors` - (Optional) A `cors` block as defined below.