diff --git a/packages/kit/src/cli.js b/packages/kit/src/cli.js
index 3f2784f950b7..1dcff209afd4 100755
--- a/packages/kit/src/cli.js
+++ b/packages/kit/src/cli.js
@@ -183,12 +183,7 @@ prog
 			// these should take precedence, but not print conflict warnings
 			if (host) vite_config.preview.host = host;
 			if (https) vite_config.preview.https = https;
-
-			if (port) {
-				vite_config.preview.port = port;
-			} else {
-				vite_config.preview.port ??= 3000;
-			}
+			if (port) vite_config.preview.port = port;
 
 			const preview_server = await vite.preview(vite_config);
 
diff --git a/packages/kit/src/vite/index.js b/packages/kit/src/vite/index.js
index cd8504dc389f..dd645d8cfa0a 100644
--- a/packages/kit/src/vite/index.js
+++ b/packages/kit/src/vite/index.js
@@ -148,6 +148,7 @@ function kit() {
 					}
 				},
 				preview: {
+					port: config.preview?.port ?? 3000,
 					strictPort: true
 				},
 				resolve: {