diff --git a/src/api.ml b/src/api.ml
index 4b43d92a..b3dd4f9b 100644
--- a/src/api.ml
+++ b/src/api.ml
@@ -523,3 +523,26 @@ module WireSetupMessage = struct
     |> mem "priority" (Jsont.option Jsont.int) ~enc:priority
     |> finish
 end
+
+module WireTeardownMessage = struct
+  type t = {
+    payto_uri: string;
+    master_sig_del: MasterDelWirePS.t;
+    (* TODO time monotonic *)
+    validity_end: Timestamp.t;
+  }
+
+  let jsont =
+    let make payto_uri master_sig_del validity_end =
+      { payto_uri; master_sig_del; validity_end }
+    in
+    let payto_uri v = v.payto_uri in
+    let master_sig_del v = v.master_sig_del in
+    let validity_end v = v.validity_end in
+    let open Jsont.Object in
+    map ~kind:"WireTeardownMessage" make
+    |> mem "payto_uri" Jsont.string ~enc:payto_uri
+    |> mem "master_sig_del" MasterDelWirePS.jsont ~enc:master_sig_del
+    |> mem "validity_end" Timestamp.jsont ~enc:validity_end
+    |> finish
+end
diff --git a/src/bin_signature.ml b/src/bin_signature.ml
index 6590b910..94195af0 100644
--- a/src/bin_signature.ml
+++ b/src/bin_signature.ml
@@ -437,6 +437,28 @@ module MasterAddWirePS = struct
   include MK (R)
 end
 
+module MasterDelWirePS = struct
+  module R = struct
+    (* purpose.purpose = TALER_SIGNATURE_MASTER_DEL_WIRE *)
+    type r = {
+      end_date: TimeAbsoluteNBO.t;
+      h_wire: FullPaytoHash.t;
+    }
+
+    let bin =
+      let open Bin in
+      Purpose.make_bin Taler_signatures.master_del_wire @@ fun _purpose ->
+      record (fun _purpose end_date h_wire -> { end_date; h_wire })
+      |+ Purpose.field _purpose
+      |+ field TimeAbsoluteNBO.bin (fun t -> t.end_date)
+      |+ field FullPaytoHash.bin (fun t -> t.h_wire)
+      |> sealr
+  end
+
+  include R
+  include MK (R)
+end
+
 (* ### BIN IMPL END ### *)
 
 module WithdrawRequestPS = struct
@@ -915,14 +937,6 @@ module CoinPurseRefundConfirmationPS = struct
   }
 end
 
-module MasterDelWirePS = struct
-  (* purpose.purpose = TALER_SIGNATURE_MASTER_DEL_WIRE *)
-  type t = {
-    end_date: TimeAbsoluteNBO.t;
-    h_wire: FullPaytoHash.t;
-  }
-end
-
 module MasterAmlOfficerStatusPS = struct
   (* purpose.purpose = TALER_SIGNATURE_MASTER_AML_KEY *)
   type t = {