diff --git a/newsfragments/3966.packaging.md b/newsfragments/3966.packaging.md
new file mode 100644
index 00000000000..81220bc4e85
--- /dev/null
+++ b/newsfragments/3966.packaging.md
@@ -0,0 +1 @@
+Update `heck` dependency to 0.5.
diff --git a/pyo3-macros-backend/Cargo.toml b/pyo3-macros-backend/Cargo.toml
index f2675f2b75e..c2ffd53b0fc 100644
--- a/pyo3-macros-backend/Cargo.toml
+++ b/pyo3-macros-backend/Cargo.toml
@@ -14,7 +14,7 @@ edition = "2021"
 # not to depend on proc-macro itself.
 # See https://github.com/PyO3/pyo3/pull/810 for more.
 [dependencies]
-heck = "0.4"
+heck = "0.5"
 proc-macro2 = { version = "1", default-features = false }
 pyo3-build-config = { path = "../pyo3-build-config", version = "=0.21.2", features = ["resolve-config"] }
 quote = { version = "1", default-features = false }