diff --git a/src/libutil/error.hh b/src/libutil/error.hh
index 417a6ad95..f402b692e 100644
--- a/src/libutil/error.hh
+++ b/src/libutil/error.hh
@@ -5,8 +5,6 @@
 #include <string>
 #include <optional>
 #include <iostream>
-#include <iomanip>
-
 #include "types.hh"
 
 namespace nix