diff --git a/common/onion_message_parse.c b/common/onion_message_parse.c
index ba0fc19aa..b7578f28a 100644
--- a/common/onion_message_parse.c
+++ b/common/onion_message_parse.c
@@ -109,7 +109,7 @@ bool onion_message_parse(const tal_t *ctx,
 
 	/* Now get onion shared secret and parse it. */
 	ecdh(&ephemeral, &onion_ss);
-	rs = process_onionpacket(tmpctx, op, &onion_ss, NULL, 0, false);
+	rs = process_onionpacket(tmpctx, op, &onion_ss, NULL, 0);
 	if (!rs) {
 		status_peer_debug(peer,
 				  "onion_message_parse: can't process onionpacket ss=%s",
diff --git a/common/sphinx.c b/common/sphinx.c
index 815e85d34..7d728bfe6 100644
--- a/common/sphinx.c
+++ b/common/sphinx.c
@@ -627,8 +627,7 @@ struct route_step *process_onionpacket(
 	const struct onionpacket *msg,
 	const struct secret *shared_secret,
 	const u8 *assocdata,
-	const size_t assocdatalen,
-	bool has_realm
+	const size_t assocdatalen
 	)
 {
 	struct route_step *step = talz(ctx, struct route_step);
diff --git a/common/sphinx.h b/common/sphinx.h
index da90e7558..6a1dbbcb0 100644
--- a/common/sphinx.h
+++ b/common/sphinx.h
@@ -107,16 +107,13 @@ bool onion_shared_secret(
  * @hoppayload: the per-hop payload destined for the processing node.
  * @assocdata: associated data to commit to in HMACs
  * @assocdatalen: length of the assocdata
- * @has_realm: used for HTLCs, where first byte 0 is magical.
  */
 struct route_step *process_onionpacket(
 	const tal_t * ctx,
 	const struct onionpacket *packet,
 	const struct secret *shared_secret,
 	const u8 *assocdata,
-	const size_t assocdatalen,
-	bool has_realm
-	);
+	const size_t assocdatalen);
 
 /**
  * serialize_onionpacket - Serialize an onionpacket to a buffer.
diff --git a/common/test/run-blindedpath_onion.c b/common/test/run-blindedpath_onion.c
index d03706150..084e1a27e 100644
--- a/common/test/run-blindedpath_onion.c
+++ b/common/test/run-blindedpath_onion.c
@@ -140,7 +140,7 @@ static u8 *next_onion(const tal_t *ctx, u8 *omsg,
 	assert(unblind_onion(&blinding, ecdh, &ephemeral, &ss));
 
 	ecdh(&ephemeral, &onion_ss);
-	rs = process_onionpacket(tmpctx, op, &onion_ss, NULL, 0, false);
+	rs = process_onionpacket(tmpctx, op, &onion_ss, NULL, 0);
 	assert(rs);
 
 	/* The raw payload is prepended with length in the modern onion. */
diff --git a/common/test/run-onion-test-vector.c b/common/test/run-onion-test-vector.c
index b68f63fe2..897b7bba3 100644
--- a/common/test/run-onion-test-vector.c
+++ b/common/test/run-onion-test-vector.c
@@ -193,7 +193,7 @@ int main(int argc, char *argv[])
 
 		json_to_secret(json, t, &mykey);
 		test_ecdh(&op->ephemeralkey, &ss);
-		rs = process_onionpacket(tmpctx, op, &ss, assoc_data, tal_bytelen(assoc_data), true);
+		rs = process_onionpacket(tmpctx, op, &ss, assoc_data, tal_bytelen(assoc_data));
 		assert(tal_arr_eq(rs->raw_payload, payloads[i]));
 		if (rs->nextcase == ONION_FORWARD)
 			op = rs->next;
diff --git a/devtools/onion.c b/devtools/onion.c
index 18430ce7c..54ef3d6e1 100644
--- a/devtools/onion.c
+++ b/devtools/onion.c
@@ -125,7 +125,7 @@ static struct route_step *decode_with_privkey(const tal_t *ctx, const u8 *onion,
 		errx(1, "Error creating shared secret.");
 
 	step = process_onionpacket(ctx, packet, &shared_secret, assocdata,
-				   tal_bytelen(assocdata), true);
+				   tal_bytelen(assocdata));
 	return step;
 
 }
diff --git a/lightningd/peer_htlcs.c b/lightningd/peer_htlcs.c
index 10b73d61f..195390362 100644
--- a/lightningd/peer_htlcs.c
+++ b/lightningd/peer_htlcs.c
@@ -1337,7 +1337,7 @@ static bool peer_accepted_htlc(const tal_t *ctx,
 
 	rs = process_onionpacket(tmpctx, op, hin->shared_secret,
 				 hin->payment_hash.u.u8,
-				 sizeof(hin->payment_hash), true);
+				 sizeof(hin->payment_hash));
 	if (!rs) {
 		*badonion = WIRE_INVALID_ONION_HMAC;
 		log_debug(channel->log,
diff --git a/wallet/test/run-wallet.c b/wallet/test/run-wallet.c
index fc759c708..4f27c95dc 100644
--- a/wallet/test/run-wallet.c
+++ b/wallet/test/run-wallet.c
@@ -915,9 +915,7 @@ struct route_step *process_onionpacket(
 	const struct onionpacket *packet UNNEEDED,
 	const struct secret *shared_secret UNNEEDED,
 	const u8 *assocdata UNNEEDED,
-	const size_t assocdatalen UNNEEDED,
-	bool has_realm
-	)
+	const size_t assocdatalen UNNEEDED)
 { fprintf(stderr, "process_onionpacket called!\n"); abort(); }
 /* Generated stub for psbt_fixup */
 const u8 *psbt_fixup(const tal_t *ctx UNNEEDED, const u8 *psbtblob UNNEEDED)