diff --git a/internal/services/appservice/helpers/function_app_schema.go b/internal/services/appservice/helpers/function_app_schema.go
index 79292d984875..871c4881990d 100644
--- a/internal/services/appservice/helpers/function_app_schema.go
+++ b/internal/services/appservice/helpers/function_app_schema.go
@@ -1595,7 +1595,7 @@ func ExpandSiteConfigLinuxFunctionApp(siteConfig []SiteConfigLinuxFunctionApp, e
 			appSettings = updateOrAppendAppSettings(appSettings, "DOCKER_REGISTRY_SERVER_URL", dockerConfig.RegistryURL, false)
 			appSettings = updateOrAppendAppSettings(appSettings, "DOCKER_REGISTRY_SERVER_USERNAME", dockerConfig.RegistryUsername, false)
 			appSettings = updateOrAppendAppSettings(appSettings, "DOCKER_REGISTRY_SERVER_PASSWORD", dockerConfig.RegistryPassword, false)
-			var dockerUrl string
+			var dockerUrl string = dockerConfig.RegistryURL
 			for _, prefix := range urlSchemes {
 				if strings.HasPrefix(dockerConfig.RegistryURL, prefix) {
 					dockerUrl = strings.TrimPrefix(dockerConfig.RegistryURL, prefix)