diff --git a/src/hooks.server.ts b/src/hooks.server.ts
index 94dc2e3..186114b 100644
--- a/src/hooks.server.ts
+++ b/src/hooks.server.ts
@@ -9,7 +9,13 @@ seedSystemTemplates().catch((e) => logger.error({ err: e }, 'Failed to seed syst
 export const handle: Handle = async ({ event, resolve }) => {
 	const start = Date.now();
 	// 1. Resolve tenant from hostname
-	const hostname = event.url.hostname;
+	// Use the Host header (or X-Forwarded-Host behind a reverse proxy)
+	// instead of event.url.hostname, which is derived from the ORIGIN env var
+	// and doesn't reflect the actual domain the user visited.
+	const hostHeader = event.request.headers.get('x-forwarded-host')
+		|| event.request.headers.get('host')
+		|| event.url.hostname;
+	const hostname = hostHeader.split(':')[0];
 	const tenant = await resolveTenant(hostname);
 	event.locals.tenant = tenant;