diff --git a/p/vbb/index.js b/p/vbb/index.js
index c3adbf4c..e426ff23 100644
--- a/p/vbb/index.js
+++ b/p/vbb/index.js
@@ -86,14 +86,13 @@ const parseDepartureRenameRingbahn = ({parsed}) => {
 
 const validIBNR = /^\d+$/
 const formatStation = (id) => {
-	if ('string' !== typeof id) throw new Error('station ID must be a string.')
-	const l = id.length
-	if ((l !== 7 && l !== 9 && l !== 12) || !validIBNR.test(id)) {
+	if ('string' !== typeof id) throw new TypeError('station ID must be a string.')
+	if (!validIBNR.test(id)) {
 		throw new Error('station ID must be a valid IBNR.')
 	}
 	// The VBB has some 7-digit stations. We don't convert them to 12 digits,
 	// because it only recognizes in the 7-digit format. see derhuerst/vbb-hafas#22
-	if (l !== 7) id = to9Digit(id)
+	if (id.length !== 7) id = to9Digit(id)
 	return _formatStation(id)
 }