diff --git a/.changeset/five-turtles-rhyme.md b/.changeset/five-turtles-rhyme.md
new file mode 100644
index 000000000000..a7095d115b91
--- /dev/null
+++ b/.changeset/five-turtles-rhyme.md
@@ -0,0 +1,5 @@
+---
+'@sveltejs/kit': patch
+---
+
+[fix] correctly populate `event.url.host` in dev mode when using `--https`
diff --git a/packages/kit/src/core/dev/plugin.js b/packages/kit/src/core/dev/plugin.js
index 9a05216b9ba1..d493af9c9a3e 100644
--- a/packages/kit/src/core/dev/plugin.js
+++ b/packages/kit/src/core/dev/plugin.js
@@ -197,7 +197,9 @@ export async function create_plugin(config, cwd) {
 					try {
 						if (!req.url || !req.method) throw new Error('Incomplete request');
 
-						const base = `${vite.config.server.https ? 'https' : 'http'}://${req.headers.host}`;
+						const base = `${vite.config.server.https ? 'https' : 'http'}://${
+							req.headers[':authority'] || req.headers.host
+						}`;
 
 						const decoded = decodeURI(new URL(base + req.url).pathname);