diff --git a/serde/src/lib.rs b/serde/src/lib.rs
index 2ecd55b00..94f5e94d0 100644
--- a/serde/src/lib.rs
+++ b/serde/src/lib.rs
@@ -120,6 +120,7 @@
         zero_prefixed_literal,
         // correctly used
         enum_glob_use,
+        let_underscore_drop,
         map_err_ignore,
         result_unit_err,
         wildcard_imports,
diff --git a/serde_derive/src/lib.rs b/serde_derive/src/lib.rs
index f4a93ae1a..ecae87835 100644
--- a/serde_derive/src/lib.rs
+++ b/serde_derive/src/lib.rs
@@ -38,6 +38,7 @@
     clippy::filter_map,
     clippy::indexing_slicing,
     clippy::items_after_statements,
+    clippy::let_underscore_drop,
     clippy::map_err_ignore,
     clippy::match_same_arms,
     clippy::module_name_repetitions,
diff --git a/serde_derive_internals/lib.rs b/serde_derive_internals/lib.rs
index f9d4a9c7c..6b78b34ae 100644
--- a/serde_derive_internals/lib.rs
+++ b/serde_derive_internals/lib.rs
@@ -18,6 +18,7 @@
     clippy::doc_markdown,
     clippy::enum_glob_use,
     clippy::items_after_statements,
+    clippy::let_underscore_drop,
     clippy::match_same_arms,
     clippy::missing_errors_doc,
     clippy::module_name_repetitions,