diff --git a/tests/fuzz/fuzz-wire-funding_signed.c b/tests/fuzz/fuzz-wire-funding_signed.c
new file mode 100644
index 000000000..4d5915238
--- /dev/null
+++ b/tests/fuzz/fuzz-wire-funding_signed.c
@@ -0,0 +1,35 @@
+#include "config.h"
+#include <tests/fuzz/libfuzz.h>
+#include <tests/fuzz/wire.h>
+#include <wire/peer_wire.h>
+
+struct funding_signed {
+	struct channel_id channel_id;
+	secp256k1_ecdsa_signature signature;
+};
+
+static void *encode(const tal_t *ctx, const struct funding_signed *s)
+{
+	return towire_funding_signed(ctx, &s->channel_id, &s->signature);
+}
+
+static struct funding_signed *decode(const tal_t *ctx, const void *p)
+{
+	struct funding_signed *s = tal(ctx, struct funding_signed);
+
+	if (fromwire_funding_signed(p, &s->channel_id, &s->signature))
+		return s;
+	return tal_free(s);
+}
+
+static bool equal(const struct funding_signed *x,
+		  const struct funding_signed *y)
+{
+	return memcmp(x, y, sizeof(*x)) == 0;
+}
+
+void run(const u8 *data, size_t size)
+{
+	test_decode_encode(data, size, WIRE_FUNDING_SIGNED,
+			   struct funding_signed);
+}