diff --git a/src/bindgen/ir/field.rs b/src/bindgen/ir/field.rs
index beec5a0..a20b407 100644
--- a/src/bindgen/ir/field.rs
+++ b/src/bindgen/ir/field.rs
@@ -46,5 +46,8 @@ impl Source for Field {
     fn write<F: Write>(&self, config: &Config, out: &mut SourceWriter<F>) {
         self.documentation.write(config, out);
         cdecl::write_field(out, &self.ty, &self.name, config);
+        if let Some(bitfield) = self.annotations.atom("bitfield") {
+            write!(out, ": {}", bitfield.unwrap_or_default());
+        }
     }
 }
diff --git a/tests/expectations/bitfield.both.c b/tests/expectations/bitfield.both.c
new file mode 100644
index 0000000..bd3e3dc
--- /dev/null
+++ b/tests/expectations/bitfield.both.c
@@ -0,0 +1,11 @@
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+typedef struct HasBitfields {
+  uint64_t foo: 8;
+  uint64_t bar: 56;
+} HasBitfields;
+
+void root(const HasBitfields*);
diff --git a/tests/expectations/bitfield.both.compat.c b/tests/expectations/bitfield.both.compat.c
new file mode 100644
index 0000000..49d87e1
--- /dev/null
+++ b/tests/expectations/bitfield.both.compat.c
@@ -0,0 +1,19 @@
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+typedef struct HasBitfields {
+  uint64_t foo: 8;
+  uint64_t bar: 56;
+} HasBitfields;
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+void root(const HasBitfields*);
+
+#ifdef __cplusplus
+} // extern "C"
+#endif // __cplusplus
diff --git a/tests/expectations/bitfield.c b/tests/expectations/bitfield.c
new file mode 100644
index 0000000..d54fa5a
--- /dev/null
+++ b/tests/expectations/bitfield.c
@@ -0,0 +1,11 @@
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+typedef struct {
+  uint64_t foo: 8;
+  uint64_t bar: 56;
+} HasBitfields;
+
+void root(const HasBitfields*);
diff --git a/tests/expectations/bitfield.compat.c b/tests/expectations/bitfield.compat.c
new file mode 100644
index 0000000..aa906fa
--- /dev/null
+++ b/tests/expectations/bitfield.compat.c
@@ -0,0 +1,19 @@
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+typedef struct {
+  uint64_t foo: 8;
+  uint64_t bar: 56;
+} HasBitfields;
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+void root(const HasBitfields*);
+
+#ifdef __cplusplus
+} // extern "C"
+#endif // __cplusplus
diff --git a/tests/expectations/bitfield.cpp b/tests/expectations/bitfield.cpp
new file mode 100644
index 0000000..3deb53f
--- /dev/null
+++ b/tests/expectations/bitfield.cpp
@@ -0,0 +1,16 @@
+#include <cstdarg>
+#include <cstdint>
+#include <cstdlib>
+#include <ostream>
+#include <new>
+
+struct HasBitfields {
+  uint64_t foo: 8;
+  uint64_t bar: 56;
+};
+
+extern "C" {
+
+void root(const HasBitfields*);
+
+} // extern "C"
diff --git a/tests/expectations/bitfield.tag.c b/tests/expectations/bitfield.tag.c
new file mode 100644
index 0000000..db327af
--- /dev/null
+++ b/tests/expectations/bitfield.tag.c
@@ -0,0 +1,11 @@
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+struct HasBitfields {
+  uint64_t foo: 8;
+  uint64_t bar: 56;
+};
+
+void root(const struct HasBitfields*);
diff --git a/tests/expectations/bitfield.tag.compat.c b/tests/expectations/bitfield.tag.compat.c
new file mode 100644
index 0000000..6aa8aed
--- /dev/null
+++ b/tests/expectations/bitfield.tag.compat.c
@@ -0,0 +1,19 @@
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+struct HasBitfields {
+  uint64_t foo: 8;
+  uint64_t bar: 56;
+};
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+void root(const struct HasBitfields*);
+
+#ifdef __cplusplus
+} // extern "C"
+#endif // __cplusplus
diff --git a/tests/rust/bitfield/Cargo.lock b/tests/rust/bitfield/Cargo.lock
new file mode 100644
index 0000000..6594121
--- /dev/null
+++ b/tests/rust/bitfield/Cargo.lock
@@ -0,0 +1,5 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+[[package]]
+name = "bitfield"
+version = "0.1.0"
diff --git a/tests/rust/bitfield/Cargo.toml b/tests/rust/bitfield/Cargo.toml
new file mode 100644
index 0000000..18a11a1
--- /dev/null
+++ b/tests/rust/bitfield/Cargo.toml
@@ -0,0 +1,7 @@
+[package]
+name = "bitfield"
+version = "0.1.0"
+authors = ["cbindgen"]
+
+[features]
+cbindgen = []
diff --git a/tests/rust/bitfield/cbindgen.toml b/tests/rust/bitfield/cbindgen.toml
new file mode 100644
index 0000000..27c92c8
--- /dev/null
+++ b/tests/rust/bitfield/cbindgen.toml
@@ -0,0 +1,3 @@
+[parse.expand]
+crates = ["bitfield"]
+features = ["cbindgen"]
diff --git a/tests/rust/bitfield/src/lib.rs b/tests/rust/bitfield/src/lib.rs
new file mode 100644
index 0000000..2369213
--- /dev/null
+++ b/tests/rust/bitfield/src/lib.rs
@@ -0,0 +1,15 @@
+#[repr(C)]
+pub struct HasBitfields {
+    #[cfg(not(feature = "cbindgen"))]
+    foo_and_bar: u64,
+
+    #[cfg(feature = "cbindgen")]
+    /// cbindgen:bitfield=8
+    foo: u64,
+    #[cfg(feature = "cbindgen")]
+    /// cbindgen:bitfield=56
+    bar: u64,
+}
+
+#[no_mangle]
+pub extern "C" fn root(_: &HasBitfields) {}