diff --git a/debian/changelog b/debian/changelog
index 5372f88b..bb6f3986 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,6 +1,7 @@
 llvm-toolchain-13 (1:13.0.0-8) UNRELEASED; urgency=medium
 
   * Trim trailing whitespace.
+  * Update watch file format version to 4.
 
  -- Sylvestre Ledru <sylvestre@debian.org>  Wed, 20 Oct 2021 23:08:57 -0000
 
diff --git a/debian/watch b/debian/watch
index a6d1751f..abd072ff 100644
--- a/debian/watch
+++ b/debian/watch
@@ -1,3 +1,2 @@
-version=3
+version=4
 https://llvm.org/releases/download.html .*/llvm-([\d\.\-]+).src.tar.xz
-