diff --git a/contrib/pyln-client/pyln/client/lightning.py b/contrib/pyln-client/pyln/client/lightning.py
index 5ca8c2117..f80006e91 100644
--- a/contrib/pyln-client/pyln/client/lightning.py
+++ b/contrib/pyln-client/pyln/client/lightning.py
@@ -2,7 +2,6 @@ import json
 import logging
 import os
 import socket
-import warnings
 from contextlib import contextmanager
 from decimal import Decimal
 from json import JSONEncoder
@@ -757,33 +756,15 @@ class LightningRpc(UnixDomainSocketRpc):
         }
         return self.call("fundchannel_cancel", payload)
 
-    def _deprecated_fundchannel_complete(self, node_id, funding_txid, funding_txout):
-        warnings.warn("fundchannel_complete: funding_txid & funding_txout replaced by psbt: expect removal"
-                      " in Mid-2021",
-                      DeprecationWarning)
-
-        payload = {
-            "id": node_id,
-            "txid": funding_txid,
-            "txout": funding_txout,
-        }
-        return self.call("fundchannel_complete", payload)
-
-    def fundchannel_complete(self, node_id, *args, **kwargs):
+    def fundchannel_complete(self, node_id, psbt):
         """
         Complete channel establishment with {id}, using {psbt}.
         """
-        if 'txid' in kwargs or len(args) == 2:
-            return self._deprecated_fundchannel_complete(node_id, *args, **kwargs)
-
-        def _fundchannel_complete(node_id, psbt):
-            payload = {
-                "id": node_id,
-                "psbt": psbt,
-            }
-            return self.call("fundchannel_complete", payload)
-
-        return _fundchannel_complete(node_id, *args, **kwargs)
+        payload = {
+            "id": node_id,
+            "psbt": psbt,
+        }
+        return self.call("fundchannel_complete", payload)
 
     def getinfo(self):
         """
diff --git a/lightningd/opening_control.c b/lightningd/opening_control.c
index 3b5b6e61d..4df90dc51 100644
--- a/lightningd/opening_control.c
+++ b/lightningd/opening_control.c
@@ -974,34 +974,12 @@ static struct command_result *json_fundchannel_complete(struct command *cmd,
 	struct wally_psbt *funding_psbt;
 	u32 *funding_txout_num = NULL;
 	struct funding_channel *fc;
-	bool old_api;
 
-	/* params is NULL for initial parameter desc generation! */
-	if (params && deprecated_apis) {
-		/* We used to have a three-arg version. */
-		if (params->type == JSMN_ARRAY)
-			old_api = (params->size == 3);
-		else
-			old_api = (json_get_member(buffer, params, "txid")
-				   != NULL);
-		if (old_api) {
-			if (!param(cmd, buffer, params,
-				   p_req("id", param_node_id, &id),
-				   p_req("txid", param_txid, &funding_txid),
-				   p_req("txout", param_number, &funding_txout_num),
-				   NULL))
-				return command_param_failed();
-		}
-	} else
-		old_api = false;
-
-	if (!old_api) {
-		if (!param(cmd, buffer, params,
-			   p_req("id", param_node_id, &id),
-			   p_req("psbt", param_psbt, &funding_psbt),
-			   NULL))
-			return command_param_failed();
-	}
+	if (!param(cmd, buffer, params,
+		   p_req("id", param_node_id, &id),
+		   p_req("psbt", param_psbt, &funding_psbt),
+		   NULL))
+		return command_param_failed();
 
 	peer = peer_by_id(cmd->ld, id);
 	if (!peer) {
@@ -1024,40 +1002,38 @@ static struct command_result *json_fundchannel_complete(struct command *cmd,
 
 	fc = peer->uncommitted_channel->fc;
 
-	if (!old_api) {
-		/* Figure out the correct output, and perform sanity checks. */
-		for (size_t i = 0; i < funding_psbt->tx->num_outputs; i++) {
-			if (memeq(funding_psbt->tx->outputs[i].script,
-				  funding_psbt->tx->outputs[i].script_len,
-				  fc->funding_scriptpubkey,
-				  tal_bytelen(fc->funding_scriptpubkey))) {
-				if (funding_txout_num)
-					return command_fail(cmd, FUNDING_PSBT_INVALID,
-							    "Two outputs to open channel");
-				funding_txout_num = tal(cmd, u32);
-				*funding_txout_num = i;
-			}
+	/* Figure out the correct output, and perform sanity checks. */
+	for (size_t i = 0; i < funding_psbt->tx->num_outputs; i++) {
+		if (memeq(funding_psbt->tx->outputs[i].script,
+			  funding_psbt->tx->outputs[i].script_len,
+			  fc->funding_scriptpubkey,
+			  tal_bytelen(fc->funding_scriptpubkey))) {
+			if (funding_txout_num)
+				return command_fail(cmd, FUNDING_PSBT_INVALID,
+						    "Two outputs to open channel");
+			funding_txout_num = tal(cmd, u32);
+			*funding_txout_num = i;
 		}
-		if (!funding_txout_num)
-			return command_fail(cmd, FUNDING_PSBT_INVALID,
-					    "No output to open channel");
-
-		/* Can't really check amounts for elements. */
-		if (!chainparams->is_elements
-		    && !amount_sat_eq(amount_sat(funding_psbt->tx->outputs
-						 [*funding_txout_num].satoshi),
-				      fc->funding_sats))
-			return command_fail(cmd, FUNDING_PSBT_INVALID,
-					    "Output to open channel is %"PRIu64"sat,"
-					    " should be %s",
-					    funding_psbt->tx->outputs
-					    [*funding_txout_num].satoshi,
-					    type_to_string(tmpctx, struct amount_sat,
-							   &fc->funding_sats));
-
-		funding_txid = tal(cmd, struct bitcoin_txid);
-		psbt_txid(NULL, funding_psbt, funding_txid, NULL);
 	}
+	if (!funding_txout_num)
+		return command_fail(cmd, FUNDING_PSBT_INVALID,
+				    "No output to open channel");
+
+	/* Can't really check amounts for elements. */
+	if (!chainparams->is_elements
+	    && !amount_sat_eq(amount_sat(funding_psbt->tx->outputs
+					 [*funding_txout_num].satoshi),
+			      fc->funding_sats))
+		return command_fail(cmd, FUNDING_PSBT_INVALID,
+				    "Output to open channel is %"PRIu64"sat,"
+				    " should be %s",
+				    funding_psbt->tx->outputs
+				    [*funding_txout_num].satoshi,
+				    type_to_string(tmpctx, struct amount_sat,
+						   &fc->funding_sats));
+
+	funding_txid = tal(cmd, struct bitcoin_txid);
+	psbt_txid(NULL, funding_psbt, funding_txid, NULL);
 
 	/* Fun fact: our wire protocol only allows 16 bits for outnum.
 	 * That is reflected in our encoding scheme for short_channel_id. */