diff --git a/components/timezone/src/ids.rs b/components/timezone/src/ids.rs
index 2916964b4bf..997e64d3964 100644
--- a/components/timezone/src/ids.rs
+++ b/components/timezone/src/ids.rs
@@ -194,7 +194,7 @@ impl TimeZoneIdMapperBorrowed<'_> {
     /// Gets the BCP-47 time zone ID from an IANA time zone ID
     /// with a case-insensitive lookup.
     ///
-    /// Returns `None` if the IANA ID is not found.
+    /// Returns [`TimeZoneBcp47Id::unknown()`] if the IANA ID is not found.
     ///
     /// # Examples
     ///