diff --git a/src/qt/psbtoperationsdialog.cpp b/src/qt/psbtoperationsdialog.cpp
index 289fb9f7c84..34d56e5506a 100644
--- a/src/qt/psbtoperationsdialog.cpp
+++ b/src/qt/psbtoperationsdialog.cpp
@@ -71,6 +71,9 @@ void PSBTOperationsDialog::signTransaction()
 {
     bool complete;
     size_t n_signed;
+
+    WalletModel::UnlockContext ctx(m_wallet_model->requestUnlock());
+
     TransactionError err = m_wallet_model->wallet().fillPSBT(SIGHASH_ALL, true /* sign */, true /* bip32derivs */, &n_signed, m_transaction_data, complete);
 
     if (err != TransactionError::OK) {
@@ -81,7 +84,9 @@ void PSBTOperationsDialog::signTransaction()
 
     updateTransactionDisplay();
 
-    if (!complete && n_signed < 1) {
+    if (!complete && !ctx.isValid()) {
+        showStatus(tr("Cannot sign inputs while wallet is locked."), StatusLevel::WARN);
+    } else if (!complete && n_signed < 1) {
         showStatus(tr("Could not sign any more inputs."), StatusLevel::WARN);
     } else if (!complete) {
         showStatus(tr("Signed %1 inputs, but more signatures are still required.").arg(n_signed),
diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
index c101f6560de..c430b1db5c6 100644
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -4420,7 +4420,7 @@ static RPCHelpMan walletprocesspsbt()
         HELP_REQUIRING_PASSPHRASE,
                 {
                     {"psbt", RPCArg::Type::STR, RPCArg::Optional::NO, "The transaction base64 string"},
-                    {"sign", RPCArg::Type::BOOL, RPCArg::Default{true}, "Also sign the transaction when updating"},
+                    {"sign", RPCArg::Type::BOOL, RPCArg::Default{true}, "Also sign the transaction when updating (requires wallet to be unlocked)"},
                     {"sighashtype", RPCArg::Type::STR, RPCArg::Default{"DEFAULT"}, "The signature hash type to sign with if not specified by the PSBT. Must be one of\n"
             "       \"DEFAULT\"\n"
             "       \"ALL\"\n"
@@ -4467,6 +4467,9 @@ static RPCHelpMan walletprocesspsbt()
     bool sign = request.params[1].isNull() ? true : request.params[1].get_bool();
     bool bip32derivs = request.params[3].isNull() ? true : request.params[3].get_bool();
     bool complete = true;
+
+    if (sign) EnsureWalletIsUnlocked(*pwallet);
+
     const TransactionError err{wallet.FillPSBT(psbtx, complete, nHashType, sign, bip32derivs)};
     if (err != TransactionError::OK) {
         throw JSONRPCTransactionError(err);
diff --git a/test/functional/rpc_psbt.py b/test/functional/rpc_psbt.py
index 2b1892c1214..f330bbf1c32 100755
--- a/test/functional/rpc_psbt.py
+++ b/test/functional/rpc_psbt.py
@@ -108,6 +108,16 @@ class PSBTTest(BitcoinTestFramework):
         psbtx = self.nodes[1].walletprocesspsbt(psbtx1)['psbt']
         assert_equal(psbtx1, psbtx)
 
+        # Node 0 should not be able to sign the transaction with the wallet is locked
+        self.nodes[0].encryptwallet("password")
+        assert_raises_rpc_error(-13, "Please enter the wallet passphrase with walletpassphrase first", self.nodes[0].walletprocesspsbt, psbtx)
+
+        # Node 0 should be able to process without signing though
+        unsigned_tx = self.nodes[0].walletprocesspsbt(psbtx, False)
+        assert_equal(unsigned_tx['complete'], False)
+
+        self.nodes[0].walletpassphrase(passphrase="password", timeout=1000000)
+
         # Sign the transaction and send
         signed_tx = self.nodes[0].walletprocesspsbt(psbtx)['psbt']
         final_tx = self.nodes[0].finalizepsbt(signed_tx)['hex']