diff --git a/src/rpc/rawtransaction_util.cpp b/src/rpc/rawtransaction_util.cpp
--- a/src/rpc/rawtransaction_util.cpp
+++ b/src/rpc/rawtransaction_util.cpp
@@ -22,13 +22,19 @@
                                          const UniValue &inputs_in,
                                          const UniValue &outputs_in,
                                          const UniValue &locktime) {
-    if (inputs_in.isNull() || outputs_in.isNull()) {
+    if (outputs_in.isNull()) {
         throw JSONRPCError(
             RPC_INVALID_PARAMETER,
-            "Invalid parameter, arguments 1 and 2 must be non-null");
+            "Invalid parameter, output argument must be non-null");
+    }
+
+    UniValue inputs;
+    if (inputs_in.isNull()) {
+        inputs = UniValue::VARR;
+    } else {
+        inputs = inputs_in.get_array();
     }
 
-    UniValue inputs = inputs_in.get_array();
     const bool outputs_is_obj = outputs_in.isObject();
     UniValue outputs =
         outputs_is_obj ? outputs_in.get_obj() : outputs_in.get_array();
diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -4736,9 +4736,9 @@
             {
                 "inputs",
                 RPCArg::Type::ARR,
-                RPCArg::Optional::NO,
-                "The inputs. Leave empty to add inputs automatically. See "
-                "add_inputs option.",
+                RPCArg::Optional::OMITTED_NAMED_ARG,
+                "Leave empty to add inputs automatically. See add_inputs "
+                "option.",
                 {
                     {
                         "",
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -353,8 +353,8 @@
                 } else {
                     for (auto spk_man : wallet->GetActiveScriptPubKeyMans()) {
                         if (!spk_man->SetupGeneration()) {
-                            error = Untranslated(
-                                "Unable to generate initial keys");
+                            error =
+                                Untranslated("Unable to generate initial keys");
                             status = DatabaseStatus::FAILED_CREATE;
                             return nullptr;
                         }
diff --git a/test/functional/rpc_psbt.py b/test/functional/rpc_psbt.py
--- a/test/functional/rpc_psbt.py
+++ b/test/functional/rpc_psbt.py
@@ -48,6 +48,10 @@
                                                       self.nodes[2].getnewaddress(): 90000000}, 0, {"add_inputs": True})['psbt']
         assert_equal(len(self.nodes[0].decodepsbt(psbtx1)['tx']['vin']), 2)
 
+        # Inputs argument can be null
+        self.nodes[0].walletcreatefundedpsbt(
+            None, {self.nodes[2].getnewaddress(): 10})
+
         # Node 1 should not be able to add anything to it but still return the
         # psbtx same as before
         psbtx = self.nodes[1].walletprocesspsbt(psbtx1)['psbt']