diff --git a/src/UDP.ml b/src/UDP.ml
index 278f97d5..a7ed5cfe 100644
--- a/src/UDP.ml
+++ b/src/UDP.ml
@@ -134,6 +134,7 @@ struct
   type t = [
     | `PARTIAL
     | `MMSG_CHUNK
+    | `MMSG_FREE
   ]
 end
 
@@ -186,6 +187,7 @@ let recv_start ?(allocate = Buffer.create) udp callback =
         []
         |> convert_flag C.Types.UDP.Flag.partial `PARTIAL
         |> convert_flag C.Types.UDP.Flag.mmsg_chunk `MMSG_CHUNK
+        |> convert_flag C.Types.UDP.Flag.mmsg_free `MMSG_FREE
       in
       Error.catch_exceptions callback (Result.Ok (buffer, sockaddr, flags))
     end
diff --git a/src/UDP.mli b/src/UDP.mli
index ebcd5ef5..6096383d 100644
--- a/src/UDP.mli
+++ b/src/UDP.mli
@@ -135,6 +135,7 @@ sig
   type t = [
     | `PARTIAL
     | `MMSG_CHUNK
+    | `MMSG_FREE
   ]
 end
 
diff --git a/src/c/luv_c_type_descriptions.ml b/src/c/luv_c_type_descriptions.ml
index 618b33ff..0caf1c7d 100644
--- a/src/c/luv_c_type_descriptions.ml
+++ b/src/c/luv_c_type_descriptions.ml
@@ -613,6 +613,7 @@ struct
       let partial = constant "UV_UDP_PARTIAL" int
       let reuseaddr = constant "UV_UDP_REUSEADDR" int
       let mmsg_chunk = constant "UV_UDP_MMSG_CHUNK" int
+      let mmsg_free = constant "UV_UDP_MMSG_FREE" int
       let recvmmsg = constant "UV_UDP_RECVMMSG" int
     end