diff --git a/serde/src/lib.rs b/serde/src/lib.rs
index e37afe010..8adb9cedb 100644
--- a/serde/src/lib.rs
+++ b/serde/src/lib.rs
@@ -130,6 +130,7 @@
         derive_partial_eq_without_eq,
         enum_glob_use,
         explicit_auto_deref,
+        let_underscore_untyped,
         map_err_ignore,
         new_without_default,
         result_unit_err,
diff --git a/serde_derive/src/lib.rs b/serde_derive/src/lib.rs
index 410078911..907f7fde4 100644
--- a/serde_derive/src/lib.rs
+++ b/serde_derive/src/lib.rs
@@ -43,6 +43,7 @@
     clippy::enum_glob_use,
     clippy::indexing_slicing,
     clippy::items_after_statements,
+    clippy::let_underscore_untyped,
     clippy::manual_assert,
     clippy::map_err_ignore,
     clippy::match_same_arms,
diff --git a/serde_derive_internals/lib.rs b/serde_derive_internals/lib.rs
index cc1c19294..3bba7b4f8 100644
--- a/serde_derive_internals/lib.rs
+++ b/serde_derive_internals/lib.rs
@@ -22,6 +22,7 @@
     clippy::doc_markdown,
     clippy::enum_glob_use,
     clippy::items_after_statements,
+    clippy::let_underscore_untyped,
     clippy::manual_assert,
     clippy::match_same_arms,
     // clippy bug: https://github.com/rust-lang/rust-clippy/issues/6984