diff --git a/src/common/messages.cpp b/src/common/messages.cpp
index 5fe3e9e4d86..fc0b4a8861f 100644
--- a/src/common/messages.cpp
+++ b/src/common/messages.cpp
@@ -116,6 +116,10 @@ bilingual_str PSBTErrorString(PSBTError err)
             return Untranslated("External signer failed to sign");
         case PSBTError::UNSUPPORTED:
             return Untranslated("Signer does not support PSBT");
+        case PSBTError::INCOMPLETE:
+            return Untranslated("Input needs additional signatures or other data");
+        case PSBTError::OK:
+            return Untranslated("No errors");
         // no default case, so the compiler can warn about missing cases
     }
     assert(false);
diff --git a/src/common/types.h b/src/common/types.h
index 0d9cb67ce94..fb9ee4bf31b 100644
--- a/src/common/types.h
+++ b/src/common/types.h
@@ -20,6 +20,8 @@ enum class PSBTError {
     EXTERNAL_SIGNER_NOT_FOUND,
     EXTERNAL_SIGNER_FAILED,
     UNSUPPORTED,
+    INCOMPLETE,
+    OK,
 };
 } // namespace common
 
diff --git a/src/interfaces/wallet.h b/src/interfaces/wallet.h
index 87f8c35a14c..7ea1a9014ae 100644
--- a/src/interfaces/wallet.h
+++ b/src/interfaces/wallet.h
@@ -207,7 +207,7 @@ public:
         int& num_blocks) = 0;
 
     //! Fill PSBT.
-    virtual std::optional<common::PSBTError> fillPSBT(int sighash_type,
+    virtual std::optional<common::PSBTError> fillPSBT(std::optional<int> sighash_type,
         bool sign,
         bool bip32derivs,
         size_t* n_signed,
diff --git a/src/node/psbt.cpp b/src/node/psbt.cpp
index 51e252bffca..3933202e0c8 100644
--- a/src/node/psbt.cpp
+++ b/src/node/psbt.cpp
@@ -64,7 +64,7 @@ PSBTAnalysis AnalyzePSBT(PartiallySignedTransaction psbtx)
 
             // Figure out what is missing
             SignatureData outdata;
-            bool complete = SignPSBTInput(DUMMY_SIGNING_PROVIDER, psbtx, i, &txdata, 1, &outdata);
+            bool complete = SignPSBTInput(DUMMY_SIGNING_PROVIDER, psbtx, i, &txdata, std::nullopt, &outdata) == PSBTError::OK;
 
             // Things are missing
             if (!complete) {
@@ -124,7 +124,7 @@ PSBTAnalysis AnalyzePSBT(PartiallySignedTransaction psbtx)
             PSBTInput& input = psbtx.inputs[i];
             Coin newcoin;
 
-            if (!SignPSBTInput(DUMMY_SIGNING_PROVIDER, psbtx, i, nullptr, 1) || !psbtx.GetInputUTXO(newcoin.out, i)) {
+            if (SignPSBTInput(DUMMY_SIGNING_PROVIDER, psbtx, i, nullptr, std::nullopt) != PSBTError::OK || !psbtx.GetInputUTXO(newcoin.out, i)) {
                 success = false;
                 break;
             } else {
diff --git a/src/psbt.cpp b/src/psbt.cpp
index 19d855e4c78..6a1f578fec2 100644
--- a/src/psbt.cpp
+++ b/src/psbt.cpp
@@ -4,12 +4,15 @@
 
 #include <psbt.h>
 
+#include <common/types.h>
 #include <node/types.h>
 #include <policy/policy.h>
 #include <script/signingprovider.h>
 #include <util/check.h>
 #include <util/strencodings.h>
 
+using common::PSBTError;
+
 PartiallySignedTransaction::PartiallySignedTransaction(const CMutableTransaction& tx) : tx(tx)
 {
     inputs.resize(tx.vin.size());
@@ -372,13 +375,13 @@ PrecomputedTransactionData PrecomputePSBTData(const PartiallySignedTransaction&
     return txdata;
 }
 
-bool SignPSBTInput(const SigningProvider& provider, PartiallySignedTransaction& psbt, int index, const PrecomputedTransactionData* txdata, int sighash,  SignatureData* out_sigdata, bool finalize)
+PSBTError SignPSBTInput(const SigningProvider& provider, PartiallySignedTransaction& psbt, int index, const PrecomputedTransactionData* txdata, std::optional<int> sighash,  SignatureData* out_sigdata, bool finalize)
 {
     PSBTInput& input = psbt.inputs.at(index);
     const CMutableTransaction& tx = *psbt.tx;
 
     if (PSBTInputSignedAndVerified(psbt, index, txdata)) {
-        return true;
+        return PSBTError::OK;
     }
 
     // Fill SignatureData with input info
@@ -393,10 +396,10 @@ bool SignPSBTInput(const SigningProvider& provider, PartiallySignedTransaction&
         // If we're taking our information from a non-witness UTXO, verify that it matches the prevout.
         COutPoint prevout = tx.vin[index].prevout;
         if (prevout.n >= input.non_witness_utxo->vout.size()) {
-            return false;
+            return PSBTError::MISSING_INPUTS;
         }
         if (input.non_witness_utxo->GetHash() != prevout.hash) {
-            return false;
+            return PSBTError::MISSING_INPUTS;
         }
         utxo = input.non_witness_utxo->vout[prevout.n];
     } else if (!input.witness_utxo.IsNull()) {
@@ -407,7 +410,46 @@ bool SignPSBTInput(const SigningProvider& provider, PartiallySignedTransaction&
         // a witness signature in this situation.
         require_witness_sig = true;
     } else {
-        return false;
+        return PSBTError::MISSING_INPUTS;
+    }
+
+    // Get the sighash type
+    // If both the field and the parameter are provided, they must match
+    // If only the parameter is provided, use it and add it to the PSBT if it is other than SIGHASH_DEFAULT
+    // for all input types, and not SIGHASH_ALL for non-taproot input types.
+    // If neither are provided, use SIGHASH_DEFAULT if it is taproot, and SIGHASH_ALL for everything else.
+    if (!sighash) sighash = utxo.scriptPubKey.IsPayToTaproot() ? SIGHASH_DEFAULT : SIGHASH_ALL;
+    // For user safety, the desired sighash must be provided if the PSBT wants something other than the default set in the previous line.
+    if (input.sighash_type && input.sighash_type != sighash) {
+        return PSBTError::SIGHASH_MISMATCH;
+    }
+    // Set the PSBT sighash field when sighash is not DEFAULT or ALL
+    // DEFAULT is allowed for non-taproot inputs since DEFAULT may be passed for them (e.g. the psbt being signed also has taproot inputs)
+    // Note that signing already aliases DEFAULT to ALL for non-taproot inputs.
+    if (utxo.scriptPubKey.IsPayToTaproot() ? sighash != SIGHASH_DEFAULT :
+                                            (sighash != SIGHASH_DEFAULT && sighash != SIGHASH_ALL)) {
+        input.sighash_type = sighash;
+    }
+    Assert(sighash.has_value());
+
+    // Check all existing signatures use the sighash type
+    if (sighash == SIGHASH_DEFAULT) {
+        if (!input.m_tap_key_sig.empty() && input.m_tap_key_sig.size() != 64) {
+            return PSBTError::SIGHASH_MISMATCH;
+        }
+        for (const auto& [_, sig] : input.m_tap_script_sigs) {
+            if (sig.size() != 64) return PSBTError::SIGHASH_MISMATCH;
+        }
+    } else {
+        if (!input.m_tap_key_sig.empty() && input.m_tap_key_sig.back() != *sighash) {
+            return PSBTError::SIGHASH_MISMATCH;
+        }
+        for (const auto& [_, sig] : input.m_tap_script_sigs) {
+            if (sig.back() != *sighash) return PSBTError::SIGHASH_MISMATCH;
+        }
+        for (const auto& [_, sig] : input.partial_sigs) {
+            if (sig.second.back() != *sighash) return PSBTError::SIGHASH_MISMATCH;
+        }
     }
 
     sigdata.witness = false;
@@ -415,11 +457,11 @@ bool SignPSBTInput(const SigningProvider& provider, PartiallySignedTransaction&
     if (txdata == nullptr) {
         sig_complete = ProduceSignature(provider, DUMMY_SIGNATURE_CREATOR, utxo.scriptPubKey, sigdata);
     } else {
-        MutableTransactionSignatureCreator creator(tx, index, utxo.nValue, txdata, sighash);
+        MutableTransactionSignatureCreator creator(tx, index, utxo.nValue, txdata, *sighash);
         sig_complete = ProduceSignature(provider, creator, utxo.scriptPubKey, sigdata);
     }
     // Verify that a witness signature was produced in case one was required.
-    if (require_witness_sig && !sigdata.witness) return false;
+    if (require_witness_sig && !sigdata.witness) return PSBTError::INCOMPLETE;
 
     // If we are not finalizing, set sigdata.complete to false to not set the scriptWitness
     if (!finalize && sigdata.complete) sigdata.complete = false;
@@ -442,39 +484,44 @@ bool SignPSBTInput(const SigningProvider& provider, PartiallySignedTransaction&
         out_sigdata->missing_witness_script = sigdata.missing_witness_script;
     }
 
-    return sig_complete;
+    return sig_complete ? PSBTError::OK : PSBTError::INCOMPLETE;
 }
 
-void RemoveUnnecessaryTransactions(PartiallySignedTransaction& psbtx, const int& sighash_type)
+void RemoveUnnecessaryTransactions(PartiallySignedTransaction& psbtx)
 {
-    // Only drop non_witness_utxos if sighash_type != SIGHASH_ANYONECANPAY
-    if ((sighash_type & 0x80) != SIGHASH_ANYONECANPAY) {
-        // Figure out if any non_witness_utxos should be dropped
-        std::vector<unsigned int> to_drop;
-        for (unsigned int i = 0; i < psbtx.inputs.size(); ++i) {
-            const auto& input = psbtx.inputs.at(i);
-            int wit_ver;
-            std::vector<unsigned char> wit_prog;
-            if (input.witness_utxo.IsNull() || !input.witness_utxo.scriptPubKey.IsWitnessProgram(wit_ver, wit_prog)) {
-                // There's a non-segwit input or Segwit v0, so we cannot drop any witness_utxos
-                to_drop.clear();
-                break;
-            }
-            if (wit_ver == 0) {
-                // Segwit v0, so we cannot drop any non_witness_utxos
-                to_drop.clear();
-                break;
-            }
-            if (input.non_witness_utxo) {
-                to_drop.push_back(i);
-            }
+    // Figure out if any non_witness_utxos should be dropped
+    std::vector<unsigned int> to_drop;
+    for (unsigned int i = 0; i < psbtx.inputs.size(); ++i) {
+        const auto& input = psbtx.inputs.at(i);
+        int wit_ver;
+        std::vector<unsigned char> wit_prog;
+        if (input.witness_utxo.IsNull() || !input.witness_utxo.scriptPubKey.IsWitnessProgram(wit_ver, wit_prog)) {
+            // There's a non-segwit input, so we cannot drop any non_witness_utxos
+            to_drop.clear();
+            break;
+        }
+        if (wit_ver == 0) {
+            // Segwit v0, so we cannot drop any non_witness_utxos
+            to_drop.clear();
+            break;
+        }
+        // non_witness_utxos cannot be dropped if the sighash type includes SIGHASH_ANYONECANPAY
+        // Since callers should have called SignPSBTInput which updates the sighash type in the PSBT, we only
+        // need to look at that field. If it is not present, then we can assume SIGHASH_DEFAULT or SIGHASH_ALL.
+        if (input.sighash_type != std::nullopt && (*input.sighash_type & 0x80) == SIGHASH_ANYONECANPAY) {
+            to_drop.clear();
+            break;
         }
 
-        // Drop the non_witness_utxos that we can drop
-        for (unsigned int i : to_drop) {
-            psbtx.inputs.at(i).non_witness_utxo = nullptr;
+        if (input.non_witness_utxo) {
+            to_drop.push_back(i);
         }
     }
+
+    // Drop the non_witness_utxos that we can drop
+    for (unsigned int i : to_drop) {
+        psbtx.inputs.at(i).non_witness_utxo = nullptr;
+    }
 }
 
 bool FinalizePSBT(PartiallySignedTransaction& psbtx)
@@ -486,7 +533,8 @@ bool FinalizePSBT(PartiallySignedTransaction& psbtx)
     bool complete = true;
     const PrecomputedTransactionData txdata = PrecomputePSBTData(psbtx);
     for (unsigned int i = 0; i < psbtx.tx->vin.size(); ++i) {
-        complete &= SignPSBTInput(DUMMY_SIGNING_PROVIDER, psbtx, i, &txdata, SIGHASH_ALL, nullptr, true);
+        PSBTInput& input = psbtx.inputs.at(i);
+        complete &= (SignPSBTInput(DUMMY_SIGNING_PROVIDER, psbtx, i, &txdata, input.sighash_type, nullptr, true) == PSBTError::OK);
     }
 
     return complete;
diff --git a/src/psbt.h b/src/psbt.h
index 6d49864b3cd..87ffe20a5d4 100644
--- a/src/psbt.h
+++ b/src/psbt.h
@@ -5,6 +5,7 @@
 #ifndef BITCOIN_PSBT_H
 #define BITCOIN_PSBT_H
 
+#include <common/types.h>
 #include <node/transaction.h>
 #include <policy/feerate.h>
 #include <primitives/transaction.h>
@@ -21,6 +22,8 @@ namespace node {
 enum class TransactionError;
 } // namespace node
 
+using common::PSBTError;
+
 // Magic bytes
 static constexpr uint8_t PSBT_MAGIC_BYTES[5] = {'p', 's', 'b', 't', 0xff};
 
@@ -429,6 +432,11 @@ struct PSBTInput
                     std::vector<unsigned char> sig;
                     s >> sig;
 
+                    // Check that the signature is validly encoded
+                    if (sig.empty() || !CheckSignatureEncoding(sig, SCRIPT_VERIFY_DERSIG | SCRIPT_VERIFY_STRICTENC, nullptr)) {
+                        throw std::ios_base::failure("Signature is not a valid encoding");
+                    }
+
                     // Add to list
                     partial_sigs.emplace(pubkey.GetID(), SigPair(pubkey, std::move(sig)));
                     break;
@@ -1236,10 +1244,10 @@ bool PSBTInputSignedAndVerified(const PartiallySignedTransaction psbt, unsigned
  * txdata should be the output of PrecomputePSBTData (which can be shared across
  * multiple SignPSBTInput calls). If it is nullptr, a dummy signature will be created.
  **/
-bool SignPSBTInput(const SigningProvider& provider, PartiallySignedTransaction& psbt, int index, const PrecomputedTransactionData* txdata, int sighash = SIGHASH_ALL, SignatureData* out_sigdata = nullptr, bool finalize = true);
+[[nodiscard]] PSBTError SignPSBTInput(const SigningProvider& provider, PartiallySignedTransaction& psbt, int index, const PrecomputedTransactionData* txdata, std::optional<int> sighash = std::nullopt, SignatureData* out_sigdata = nullptr, bool finalize = true);
 
 /**  Reduces the size of the PSBT by dropping unnecessary `non_witness_utxos` (i.e. complete previous transactions) from a psbt when all inputs are segwit v1. */
-void RemoveUnnecessaryTransactions(PartiallySignedTransaction& psbtx, const int& sighash_type);
+void RemoveUnnecessaryTransactions(PartiallySignedTransaction& psbtx);
 
 /** Counts the unsigned inputs of a PSBT. */
 size_t CountPSBTUnsignedInputs(const PartiallySignedTransaction& psbt);
diff --git a/src/qt/psbtoperationsdialog.cpp b/src/qt/psbtoperationsdialog.cpp
index 454d9287aea..afe6a8999ac 100644
--- a/src/qt/psbtoperationsdialog.cpp
+++ b/src/qt/psbtoperationsdialog.cpp
@@ -59,7 +59,7 @@ void PSBTOperationsDialog::openWithPSBT(PartiallySignedTransaction psbtx)
     bool complete = FinalizePSBT(psbtx); // Make sure all existing signatures are fully combined before checking for completeness.
     if (m_wallet_model) {
         size_t n_could_sign;
-        const auto err{m_wallet_model->wallet().fillPSBT(SIGHASH_ALL, /*sign=*/false, /*bip32derivs=*/true, &n_could_sign, m_transaction_data, complete)};
+        const auto err{m_wallet_model->wallet().fillPSBT(std::nullopt, /*sign=*/false, /*bip32derivs=*/true, &n_could_sign, m_transaction_data, complete)};
         if (err) {
             showStatus(tr("Failed to load transaction: %1")
                            .arg(QString::fromStdString(PSBTErrorString(*err).translated)),
@@ -83,7 +83,7 @@ void PSBTOperationsDialog::signTransaction()
 
     WalletModel::UnlockContext ctx(m_wallet_model->requestUnlock());
 
-    const auto err{m_wallet_model->wallet().fillPSBT(SIGHASH_DEFAULT, /*sign=*/true, /*bip32derivs=*/true, &n_signed, m_transaction_data, complete)};
+    const auto err{m_wallet_model->wallet().fillPSBT(std::nullopt, /*sign=*/true, /*bip32derivs=*/true, &n_signed, m_transaction_data, complete)};
 
     if (err) {
         showStatus(tr("Failed to sign transaction: %1")
@@ -251,7 +251,7 @@ size_t PSBTOperationsDialog::couldSignInputs(const PartiallySignedTransaction &p
 
     size_t n_signed;
     bool complete;
-    const auto err{m_wallet_model->wallet().fillPSBT(SIGHASH_ALL, /*sign=*/false, /*bip32derivs=*/false, &n_signed, m_transaction_data, complete)};
+    const auto err{m_wallet_model->wallet().fillPSBT(std::nullopt, /*sign=*/false, /*bip32derivs=*/false, &n_signed, m_transaction_data, complete)};
 
     if (err) {
         return 0;
diff --git a/src/qt/sendcoinsdialog.cpp b/src/qt/sendcoinsdialog.cpp
index 0ee1b359fa9..8c3797603e5 100644
--- a/src/qt/sendcoinsdialog.cpp
+++ b/src/qt/sendcoinsdialog.cpp
@@ -446,7 +446,7 @@ void SendCoinsDialog::presentPSBT(PartiallySignedTransaction& psbtx)
 bool SendCoinsDialog::signWithExternalSigner(PartiallySignedTransaction& psbtx, CMutableTransaction& mtx, bool& complete) {
     std::optional<PSBTError> err;
     try {
-        err = model->wallet().fillPSBT(SIGHASH_ALL, /*sign=*/true, /*bip32derivs=*/true, /*n_signed=*/nullptr, psbtx, complete);
+        err = model->wallet().fillPSBT(std::nullopt, /*sign=*/true, /*bip32derivs=*/true, /*n_signed=*/nullptr, psbtx, complete);
     } catch (const std::runtime_error& e) {
         QMessageBox::critical(nullptr, tr("Sign failed"), e.what());
         return false;
@@ -503,7 +503,7 @@ void SendCoinsDialog::sendButtonClicked([[maybe_unused]] bool checked)
         PartiallySignedTransaction psbtx(mtx);
         bool complete = false;
         // Fill without signing
-        const auto err{model->wallet().fillPSBT(SIGHASH_ALL, /*sign=*/false, /*bip32derivs=*/true, /*n_signed=*/nullptr, psbtx, complete)};
+        const auto err{model->wallet().fillPSBT(std::nullopt, /*sign=*/false, /*bip32derivs=*/true, /*n_signed=*/nullptr, psbtx, complete)};
         assert(!complete);
         assert(!err);
 
@@ -519,7 +519,7 @@ void SendCoinsDialog::sendButtonClicked([[maybe_unused]] bool checked)
             bool complete = false;
             // Always fill without signing first. This prevents an external signer
             // from being called prematurely and is not expensive.
-            const auto err{model->wallet().fillPSBT(SIGHASH_ALL, /*sign=*/false, /*bip32derivs=*/true, /*n_signed=*/nullptr, psbtx, complete)};
+            const auto err{model->wallet().fillPSBT(std::nullopt, /*sign=*/false, /*bip32derivs=*/true, /*n_signed=*/nullptr, psbtx, complete)};
             assert(!complete);
             assert(!err);
             send_failure = !signWithExternalSigner(psbtx, mtx, complete);
diff --git a/src/qt/walletmodel.cpp b/src/qt/walletmodel.cpp
index 0a01c0a45b1..eb68ee7142e 100644
--- a/src/qt/walletmodel.cpp
+++ b/src/qt/walletmodel.cpp
@@ -535,7 +535,7 @@ bool WalletModel::bumpFee(uint256 hash, uint256& new_hash)
         // "Create Unsigned" clicked
         PartiallySignedTransaction psbtx(mtx);
         bool complete = false;
-        const auto err{wallet().fillPSBT(SIGHASH_ALL, /*sign=*/false, /*bip32derivs=*/true, nullptr, psbtx, complete)};
+        const auto err{wallet().fillPSBT(std::nullopt, /*sign=*/false, /*bip32derivs=*/true, nullptr, psbtx, complete)};
         if (err || complete) {
             QMessageBox::critical(nullptr, tr("Fee bump error"), tr("Can't draft transaction."));
             return false;
diff --git a/src/rpc/rawtransaction.cpp b/src/rpc/rawtransaction.cpp
index 421656152cb..3cc2d61d228 100644
--- a/src/rpc/rawtransaction.cpp
+++ b/src/rpc/rawtransaction.cpp
@@ -163,7 +163,7 @@ static std::vector<RPCArg> CreateTxDoc()
 
 // Update PSBT with information from the mempool, the UTXO set, the txindex, and the provided descriptors.
 // Optionally, sign the inputs that we can using information from the descriptors.
-PartiallySignedTransaction ProcessPSBT(const std::string& psbt_string, const std::any& context, const HidingSigningProvider& provider, int sighash_type, bool finalize)
+PartiallySignedTransaction ProcessPSBT(const std::string& psbt_string, const std::any& context, const HidingSigningProvider& provider, std::optional<int> sighash_type, bool finalize)
 {
     // Unserialize the transactions
     PartiallySignedTransaction psbtx;
@@ -235,7 +235,10 @@ PartiallySignedTransaction ProcessPSBT(const std::string& psbt_string, const std
         // Note that SignPSBTInput does a lot more than just constructing ECDSA signatures.
         // We only actually care about those if our signing provider doesn't hide private
         // information, as is the case with `descriptorprocesspsbt`
-        SignPSBTInput(provider, psbtx, /*index=*/i, &txdata, sighash_type, /*out_sigdata=*/nullptr, finalize);
+        // Only error for mismatching sighash types as it is critical that the sighash to sign with matches the PSBT's
+        if (SignPSBTInput(provider, psbtx, /*index=*/i, &txdata, sighash_type, /*out_sigdata=*/nullptr, finalize) == common::PSBTError::SIGHASH_MISMATCH) {
+            throw JSONRPCPSBTError(common::PSBTError::SIGHASH_MISMATCH);
+        }
     }
 
     // Update script/keypath information using descriptor data.
@@ -243,7 +246,7 @@ PartiallySignedTransaction ProcessPSBT(const std::string& psbt_string, const std
         UpdatePSBTOutput(provider, psbtx, i);
     }
 
-    RemoveUnnecessaryTransactions(psbtx, /*sighash_type=*/1);
+    RemoveUnnecessaryTransactions(psbtx);
 
     return psbtx;
 }
@@ -1689,7 +1692,7 @@ static RPCHelpMan utxoupdatepsbt()
         request.params[0].get_str(),
         request.context,
         HidingSigningProvider(&provider, /*hide_secret=*/true, /*hide_origin=*/false),
-        /*sighash_type=*/SIGHASH_ALL,
+        /*sighash_type=*/std::nullopt,
         /*finalize=*/false);
 
     DataStream ssTx{};
@@ -1956,7 +1959,7 @@ RPCHelpMan descriptorprocesspsbt()
         EvalDescriptorStringOrObject(descs[i], provider, /*expand_priv=*/true);
     }
 
-    int sighash_type = ParseSighashString(request.params[2]);
+    std::optional<int> sighash_type = ParseSighashString(request.params[2]);
     bool bip32derivs = request.params[3].isNull() ? true : request.params[3].get_bool();
     bool finalize = request.params[4].isNull() ? true : request.params[4].get_bool();
 
diff --git a/src/rpc/rawtransaction_util.cpp b/src/rpc/rawtransaction_util.cpp
index 53f943bb9e0..17a111ae0bc 100644
--- a/src/rpc/rawtransaction_util.cpp
+++ b/src/rpc/rawtransaction_util.cpp
@@ -304,12 +304,15 @@ void ParsePrevouts(const UniValue& prevTxsUnival, FlatSigningProvider* keystore,
 
 void SignTransaction(CMutableTransaction& mtx, const SigningProvider* keystore, const std::map<COutPoint, Coin>& coins, const UniValue& hashType, UniValue& result)
 {
-    int nHashType = ParseSighashString(hashType);
+    std::optional<int> nHashType = ParseSighashString(hashType);
+    if (!nHashType) {
+        nHashType = SIGHASH_DEFAULT;
+    }
 
     // Script verification errors
     std::map<int, bilingual_str> input_errors;
 
-    bool complete = SignTransaction(mtx, keystore, coins, nHashType, input_errors);
+    bool complete = SignTransaction(mtx, keystore, coins, *nHashType, input_errors);
     SignTransactionResultToJSON(mtx, complete, coins, input_errors, result);
 }
 
diff --git a/src/rpc/util.cpp b/src/rpc/util.cpp
index 4c83517c8da..27fe1f197b8 100644
--- a/src/rpc/util.cpp
+++ b/src/rpc/util.cpp
@@ -378,10 +378,10 @@ UniValue DescribeAddress(const CTxDestination& dest)
  *
  * @pre The sighash argument should be string or null.
 */
-int ParseSighashString(const UniValue& sighash)
+std::optional<int> ParseSighashString(const UniValue& sighash)
 {
     if (sighash.isNull()) {
-        return SIGHASH_DEFAULT;
+        return std::nullopt;
     }
     const auto result{SighashFromStr(sighash.get_str())};
     if (!result) {
diff --git a/src/rpc/util.h b/src/rpc/util.h
index 4eafa1eb6e4..0c48f8aa292 100644
--- a/src/rpc/util.h
+++ b/src/rpc/util.h
@@ -138,7 +138,7 @@ CTxDestination AddAndGetMultisigDestination(const int required, const std::vecto
 UniValue DescribeAddress(const CTxDestination& dest);
 
 /** Parse a sighash string representation and raise an RPC error if it is invalid. */
-int ParseSighashString(const UniValue& sighash);
+std::optional<int> ParseSighashString(const UniValue& sighash);
 
 //! Parse a confirm target option and raise an RPC error if it is invalid.
 unsigned int ParseConfirmTarget(const UniValue& value, unsigned int max_target);
diff --git a/src/script/script.cpp b/src/script/script.cpp
index d650db9a0d6..829e351be69 100644
--- a/src/script/script.cpp
+++ b/src/script/script.cpp
@@ -238,6 +238,13 @@ bool CScript::IsPayToWitnessScriptHash() const
             (*this)[1] == 0x20);
 }
 
+bool CScript::IsPayToTaproot() const
+{
+    return (this->size() == 34 &&
+            (*this)[0] == OP_1 &&
+            (*this)[1] == 0x20);
+}
+
 // A witness program is any valid CScript that consists of a 1-byte push opcode
 // followed by a data push between 2 and 40 bytes.
 bool CScript::IsWitnessProgram(int& version, std::vector<unsigned char>& program) const
diff --git a/src/script/script.h b/src/script/script.h
index f4579849803..6104630a1ee 100644
--- a/src/script/script.h
+++ b/src/script/script.h
@@ -556,6 +556,8 @@ public:
     bool IsPayToWitnessScriptHash() const;
     bool IsWitnessProgram(int& version, std::vector<unsigned char>& program) const;
 
+    bool IsPayToTaproot() const;
+
     /** Called by IsStandardTx and P2SH/BIP62 VerifyScript (which makes it consensus-critical). */
     bool IsPushOnly(const_iterator pc) const;
     bool IsPushOnly() const;
diff --git a/src/wallet/external_signer_scriptpubkeyman.cpp b/src/wallet/external_signer_scriptpubkeyman.cpp
index 32e9941453b..7268354f1a9 100644
--- a/src/wallet/external_signer_scriptpubkeyman.cpp
+++ b/src/wallet/external_signer_scriptpubkeyman.cpp
@@ -79,7 +79,7 @@ util::Result<void> ExternalSignerScriptPubKeyMan::DisplayAddress(const CTxDestin
 }
 
 // If sign is true, transaction must previously have been filled
-std::optional<PSBTError> ExternalSignerScriptPubKeyMan::FillPSBT(PartiallySignedTransaction& psbt, const PrecomputedTransactionData& txdata, int sighash_type, bool sign, bool bip32derivs, int* n_signed, bool finalize) const
+std::optional<PSBTError> ExternalSignerScriptPubKeyMan::FillPSBT(PartiallySignedTransaction& psbt, const PrecomputedTransactionData& txdata, std::optional<int> sighash_type, bool sign, bool bip32derivs, int* n_signed, bool finalize) const
 {
     if (!sign) {
         return DescriptorScriptPubKeyMan::FillPSBT(psbt, txdata, sighash_type, false, bip32derivs, n_signed, finalize);
diff --git a/src/wallet/external_signer_scriptpubkeyman.h b/src/wallet/external_signer_scriptpubkeyman.h
index 10d67d2ab47..66c2dd9d170 100644
--- a/src/wallet/external_signer_scriptpubkeyman.h
+++ b/src/wallet/external_signer_scriptpubkeyman.h
@@ -35,7 +35,7 @@ class ExternalSignerScriptPubKeyMan : public DescriptorScriptPubKeyMan
   */
  util::Result<void> DisplayAddress(const CTxDestination& dest, const ExternalSigner& signer) const;
 
-  std::optional<common::PSBTError> FillPSBT(PartiallySignedTransaction& psbt, const PrecomputedTransactionData& txdata, int sighash_type = 1 /* SIGHASH_ALL */, bool sign = true, bool bip32derivs = false, int* n_signed = nullptr, bool finalize = true) const override;
+  std::optional<common::PSBTError> FillPSBT(PartiallySignedTransaction& psbt, const PrecomputedTransactionData& txdata, std::optional<int> sighash_type = std::nullopt, bool sign = true, bool bip32derivs = false, int* n_signed = nullptr, bool finalize = true) const override;
 };
 } // namespace wallet
 #endif // BITCOIN_WALLET_EXTERNAL_SIGNER_SCRIPTPUBKEYMAN_H
diff --git a/src/wallet/feebumper.cpp b/src/wallet/feebumper.cpp
index b875461c9f2..170941b1daf 100644
--- a/src/wallet/feebumper.cpp
+++ b/src/wallet/feebumper.cpp
@@ -343,8 +343,8 @@ bool SignTransaction(CWallet& wallet, CMutableTransaction& mtx) {
         // First fill transaction with our data without signing,
         // so external signers are not asked to sign more than once.
         bool complete;
-        wallet.FillPSBT(psbtx, complete, SIGHASH_ALL, false /* sign */, true /* bip32derivs */);
-        auto err{wallet.FillPSBT(psbtx, complete, SIGHASH_ALL, true /* sign */, false  /* bip32derivs */)};
+        wallet.FillPSBT(psbtx, complete, std::nullopt, false /* sign */, true /* bip32derivs */);
+        auto err{wallet.FillPSBT(psbtx, complete, std::nullopt, true /* sign */, false  /* bip32derivs */)};
         if (err) return false;
         complete = FinalizeAndExtractPSBT(psbtx, mtx);
         return complete;
diff --git a/src/wallet/interfaces.cpp b/src/wallet/interfaces.cpp
index 21e8a0b3bd2..d477c34d69e 100644
--- a/src/wallet/interfaces.cpp
+++ b/src/wallet/interfaces.cpp
@@ -391,7 +391,7 @@ public:
         }
         return {};
     }
-    std::optional<PSBTError> fillPSBT(int sighash_type,
+    std::optional<PSBTError> fillPSBT(std::optional<int> sighash_type,
         bool sign,
         bool bip32derivs,
         size_t* n_signed,
diff --git a/src/wallet/rpc/spend.cpp b/src/wallet/rpc/spend.cpp
index 0cba830e2ab..0dee8a89726 100644
--- a/src/wallet/rpc/spend.cpp
+++ b/src/wallet/rpc/spend.cpp
@@ -100,8 +100,8 @@ static UniValue FinishTransaction(const std::shared_ptr<CWallet> pwallet, const
     // First fill transaction with our data without signing,
     // so external signers are not asked to sign more than once.
     bool complete;
-    pwallet->FillPSBT(psbtx, complete, SIGHASH_DEFAULT, /*sign=*/false, /*bip32derivs=*/true);
-    const auto err{pwallet->FillPSBT(psbtx, complete, SIGHASH_DEFAULT, /*sign=*/true, /*bip32derivs=*/false)};
+    pwallet->FillPSBT(psbtx, complete, std::nullopt, /*sign=*/false, /*bip32derivs=*/true);
+    const auto err{pwallet->FillPSBT(psbtx, complete, std::nullopt, /*sign=*/true, /*bip32derivs=*/false)};
     if (err) {
         throw JSONRPCPSBTError(*err);
     }
@@ -951,12 +951,15 @@ RPCHelpMan signrawtransactionwithwallet()
     // Parse the prevtxs array
     ParsePrevouts(request.params[1], nullptr, coins);
 
-    int nHashType = ParseSighashString(request.params[2]);
+    std::optional<int> nHashType = ParseSighashString(request.params[2]);
+    if (!nHashType) {
+        nHashType = SIGHASH_DEFAULT;
+    }
 
     // Script verification errors
     std::map<int, bilingual_str> input_errors;
 
-    bool complete = pwallet->SignTransaction(mtx, coins, nHashType, input_errors);
+    bool complete = pwallet->SignTransaction(mtx, coins, *nHashType, input_errors);
     UniValue result(UniValue::VOBJ);
     SignTransactionResultToJSON(mtx, complete, coins, input_errors, result);
     return result;
@@ -1169,7 +1172,7 @@ static RPCHelpMan bumpfee_helper(std::string method_name)
     } else {
         PartiallySignedTransaction psbtx(mtx);
         bool complete = false;
-        const auto err{pwallet->FillPSBT(psbtx, complete, SIGHASH_DEFAULT, /*sign=*/false, /*bip32derivs=*/true)};
+        const auto err{pwallet->FillPSBT(psbtx, complete, std::nullopt, /*sign=*/false, /*bip32derivs=*/true)};
         CHECK_NONFATAL(!err);
         CHECK_NONFATAL(!complete);
         DataStream ssTx{};
@@ -1623,7 +1626,7 @@ RPCHelpMan walletprocesspsbt()
     }
 
     // Get the sighash type
-    int nHashType = ParseSighashString(request.params[2]);
+    std::optional<int> nHashType = ParseSighashString(request.params[2]);
 
     // Fill transaction with our data and also sign
     bool sign = request.params[1].isNull() ? true : request.params[1].get_bool();
@@ -1769,7 +1772,7 @@ RPCHelpMan walletcreatefundedpsbt()
     // Fill transaction with out data but don't sign
     bool bip32derivs = request.params[4].isNull() ? true : request.params[4].get_bool();
     bool complete = true;
-    const auto err{wallet.FillPSBT(psbtx, complete, 1, /*sign=*/false, /*bip32derivs=*/bip32derivs)};
+    const auto err{wallet.FillPSBT(psbtx, complete, std::nullopt, /*sign=*/false, /*bip32derivs=*/bip32derivs)};
     if (err) {
         throw JSONRPCPSBTError(*err);
     }
diff --git a/src/wallet/scriptpubkeyman.cpp b/src/wallet/scriptpubkeyman.cpp
index 04287581f5a..c30128fae5b 100644
--- a/src/wallet/scriptpubkeyman.cpp
+++ b/src/wallet/scriptpubkeyman.cpp
@@ -638,7 +638,7 @@ SigningResult LegacyScriptPubKeyMan::SignMessage(const std::string& message, con
     return SigningResult::SIGNING_FAILED;
 }
 
-std::optional<PSBTError> LegacyScriptPubKeyMan::FillPSBT(PartiallySignedTransaction& psbtx, const PrecomputedTransactionData& txdata, int sighash_type, bool sign, bool bip32derivs, int* n_signed, bool finalize) const
+std::optional<PSBTError> LegacyScriptPubKeyMan::FillPSBT(PartiallySignedTransaction& psbtx, const PrecomputedTransactionData& txdata, std::optional<int> sighash_type, bool sign, bool bip32derivs, int* n_signed, bool finalize) const
 {
     if (n_signed) {
         *n_signed = 0;
@@ -651,11 +651,6 @@ std::optional<PSBTError> LegacyScriptPubKeyMan::FillPSBT(PartiallySignedTransact
             continue;
         }
 
-        // Get the Sighash type
-        if (sign && input.sighash_type != std::nullopt && *input.sighash_type != sighash_type) {
-            return PSBTError::SIGHASH_MISMATCH;
-        }
-
         // Check non_witness_utxo has specified prevout
         if (input.non_witness_utxo) {
             if (txin.prevout.n >= input.non_witness_utxo->vout.size()) {
@@ -665,7 +660,10 @@ std::optional<PSBTError> LegacyScriptPubKeyMan::FillPSBT(PartiallySignedTransact
             // There's no UTXO so we can just skip this now
             continue;
         }
-        SignPSBTInput(HidingSigningProvider(this, !sign, !bip32derivs), psbtx, i, &txdata, sighash_type, nullptr, finalize);
+        PSBTError res = SignPSBTInput(HidingSigningProvider(this, !sign, !bip32derivs), psbtx, i, &txdata, sighash_type, nullptr, finalize);
+        if (res != PSBTError::OK && res != PSBTError::INCOMPLETE) {
+            return res;
+        }
 
         bool signed_one = PSBTInputSigned(input);
         if (n_signed && (signed_one || !sign)) {
@@ -2565,7 +2563,7 @@ SigningResult DescriptorScriptPubKeyMan::SignMessage(const std::string& message,
     return SigningResult::OK;
 }
 
-std::optional<PSBTError> DescriptorScriptPubKeyMan::FillPSBT(PartiallySignedTransaction& psbtx, const PrecomputedTransactionData& txdata, int sighash_type, bool sign, bool bip32derivs, int* n_signed, bool finalize) const
+std::optional<PSBTError> DescriptorScriptPubKeyMan::FillPSBT(PartiallySignedTransaction& psbtx, const PrecomputedTransactionData& txdata, std::optional<int> sighash_type, bool sign, bool bip32derivs, int* n_signed, bool finalize) const
 {
     if (n_signed) {
         *n_signed = 0;
@@ -2578,11 +2576,6 @@ std::optional<PSBTError> DescriptorScriptPubKeyMan::FillPSBT(PartiallySignedTran
             continue;
         }
 
-        // Get the Sighash type
-        if (sign && input.sighash_type != std::nullopt && *input.sighash_type != sighash_type) {
-            return PSBTError::SIGHASH_MISMATCH;
-        }
-
         // Get the scriptPubKey to know which SigningProvider to use
         CScript script;
         if (!input.witness_utxo.IsNull()) {
@@ -2640,7 +2633,10 @@ std::optional<PSBTError> DescriptorScriptPubKeyMan::FillPSBT(PartiallySignedTran
             }
         }
 
-        SignPSBTInput(HidingSigningProvider(keys.get(), /*hide_secret=*/!sign, /*hide_origin=*/!bip32derivs), psbtx, i, &txdata, sighash_type, nullptr, finalize);
+        PSBTError res = SignPSBTInput(HidingSigningProvider(keys.get(), /*hide_secret=*/!sign, /*hide_origin=*/!bip32derivs), psbtx, i, &txdata, sighash_type, nullptr, finalize);
+        if (res != PSBTError::OK && res != PSBTError::INCOMPLETE) {
+            return res;
+        }
 
         bool signed_one = PSBTInputSigned(input);
         if (n_signed && (signed_one || !sign)) {
diff --git a/src/wallet/scriptpubkeyman.h b/src/wallet/scriptpubkeyman.h
index 4dbb2838d71..930d21a5f50 100644
--- a/src/wallet/scriptpubkeyman.h
+++ b/src/wallet/scriptpubkeyman.h
@@ -246,7 +246,7 @@ public:
     /** Sign a message with the given script */
     virtual SigningResult SignMessage(const std::string& message, const PKHash& pkhash, std::string& str_sig) const { return SigningResult::SIGNING_FAILED; };
     /** Adds script and derivation path information to a PSBT, and optionally signs it. */
-    virtual std::optional<common::PSBTError> FillPSBT(PartiallySignedTransaction& psbt, const PrecomputedTransactionData& txdata, int sighash_type = SIGHASH_DEFAULT, bool sign = true, bool bip32derivs = false, int* n_signed = nullptr, bool finalize = true) const { return common::PSBTError::UNSUPPORTED; }
+    virtual std::optional<common::PSBTError> FillPSBT(PartiallySignedTransaction& psbt, const PrecomputedTransactionData& txdata, std::optional<int> sighash_type = std::nullopt, bool sign = true, bool bip32derivs = false, int* n_signed = nullptr, bool finalize = true) const { return common::PSBTError::UNSUPPORTED; }
 
     virtual uint256 GetID() const { return uint256(); }
 
@@ -495,7 +495,7 @@ public:
 
     bool SignTransaction(CMutableTransaction& tx, const std::map<COutPoint, Coin>& coins, int sighash, std::map<int, bilingual_str>& input_errors) const override;
     SigningResult SignMessage(const std::string& message, const PKHash& pkhash, std::string& str_sig) const override;
-    std::optional<common::PSBTError> FillPSBT(PartiallySignedTransaction& psbt, const PrecomputedTransactionData& txdata, int sighash_type = SIGHASH_DEFAULT, bool sign = true, bool bip32derivs = false, int* n_signed = nullptr, bool finalize = true) const override;
+    std::optional<common::PSBTError> FillPSBT(PartiallySignedTransaction& psbt, const PrecomputedTransactionData& txdata, std::optional<int> sighash_type = std::nullopt, bool sign = true, bool bip32derivs = false, int* n_signed = nullptr, bool finalize = true) const override;
 
     uint256 GetID() const override;
 
@@ -684,7 +684,7 @@ public:
 
     bool SignTransaction(CMutableTransaction& tx, const std::map<COutPoint, Coin>& coins, int sighash, std::map<int, bilingual_str>& input_errors) const override;
     SigningResult SignMessage(const std::string& message, const PKHash& pkhash, std::string& str_sig) const override;
-    std::optional<common::PSBTError> FillPSBT(PartiallySignedTransaction& psbt, const PrecomputedTransactionData& txdata, int sighash_type = SIGHASH_DEFAULT, bool sign = true, bool bip32derivs = false, int* n_signed = nullptr, bool finalize = true) const override;
+    std::optional<common::PSBTError> FillPSBT(PartiallySignedTransaction& psbt, const PrecomputedTransactionData& txdata, std::optional<int> sighash_type = std::nullopt, bool sign = true, bool bip32derivs = false, int* n_signed = nullptr, bool finalize = true) const override;
 
     uint256 GetID() const override;
 
diff --git a/src/wallet/test/fuzz/scriptpubkeyman.cpp b/src/wallet/test/fuzz/scriptpubkeyman.cpp
index 0c17a6bf7a9..18b3c829a46 100644
--- a/src/wallet/test/fuzz/scriptpubkeyman.cpp
+++ b/src/wallet/test/fuzz/scriptpubkeyman.cpp
@@ -188,7 +188,8 @@ FUZZ_TARGET(scriptpubkeyman, .init = initialize_spkm)
                 }
                 auto psbt{*opt_psbt};
                 const PrecomputedTransactionData txdata{PrecomputePSBTData(psbt)};
-                const int sighash_type{fuzzed_data_provider.ConsumeIntegralInRange<int>(0, 150)};
+                std::optional<int> sighash_type{fuzzed_data_provider.ConsumeIntegralInRange<int>(0, 151)};
+                if (sighash_type == 151) sighash_type = std::nullopt;
                 auto sign  = fuzzed_data_provider.ConsumeBool();
                 auto bip32derivs = fuzzed_data_provider.ConsumeBool();
                 auto finalize = fuzzed_data_provider.ConsumeBool();
diff --git a/src/wallet/test/psbt_wallet_tests.cpp b/src/wallet/test/psbt_wallet_tests.cpp
index 09057114a0b..d6cc0805100 100644
--- a/src/wallet/test/psbt_wallet_tests.cpp
+++ b/src/wallet/test/psbt_wallet_tests.cpp
@@ -64,7 +64,7 @@ BOOST_AUTO_TEST_CASE(psbt_updater_test)
 
     // Fill transaction with our data
     bool complete = true;
-    BOOST_REQUIRE(!m_wallet.FillPSBT(psbtx, complete, SIGHASH_ALL, false, true));
+    BOOST_REQUIRE(!m_wallet.FillPSBT(psbtx, complete, std::nullopt, false, true));
 
     // Get the final tx
     DataStream ssTx{};
@@ -77,7 +77,7 @@ BOOST_AUTO_TEST_CASE(psbt_updater_test)
 
     // Try to sign the mutated input
     SignatureData sigdata;
-    BOOST_CHECK(m_wallet.FillPSBT(psbtx, complete, SIGHASH_ALL, true, true));
+    BOOST_CHECK(m_wallet.FillPSBT(psbtx, complete, std::nullopt, true, true));
 }
 
 BOOST_AUTO_TEST_CASE(parse_hd_keypath)
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 09eda0c28e4..807ba255b52 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -2211,7 +2211,7 @@ bool CWallet::SignTransaction(CMutableTransaction& tx, const std::map<COutPoint,
     return false;
 }
 
-std::optional<PSBTError> CWallet::FillPSBT(PartiallySignedTransaction& psbtx, bool& complete, int sighash_type, bool sign, bool bip32derivs, size_t * n_signed, bool finalize) const
+std::optional<PSBTError> CWallet::FillPSBT(PartiallySignedTransaction& psbtx, bool& complete, std::optional<int> sighash_type, bool sign, bool bip32derivs, size_t * n_signed, bool finalize) const
 {
     if (n_signed) {
         *n_signed = 0;
@@ -2254,7 +2254,7 @@ std::optional<PSBTError> CWallet::FillPSBT(PartiallySignedTransaction& psbtx, bo
         }
     }
 
-    RemoveUnnecessaryTransactions(psbtx, sighash_type);
+    RemoveUnnecessaryTransactions(psbtx);
 
     // Complete if every input is now signed
     complete = true;
diff --git a/src/wallet/wallet.h b/src/wallet/wallet.h
index c475718eb94..81fdb4fef6c 100644
--- a/src/wallet/wallet.h
+++ b/src/wallet/wallet.h
@@ -663,7 +663,7 @@ public:
      */
     std::optional<common::PSBTError> FillPSBT(PartiallySignedTransaction& psbtx,
                   bool& complete,
-                  int sighash_type = SIGHASH_DEFAULT,
+                  std::optional<int> sighash_type = std::nullopt,
                   bool sign = true,
                   bool bip32derivs = true,
                   size_t* n_signed = nullptr,
diff --git a/test/functional/rpc_psbt.py b/test/functional/rpc_psbt.py
index 04e68a97af7..d223a1575f5 100755
--- a/test/functional/rpc_psbt.py
+++ b/test/functional/rpc_psbt.py
@@ -27,13 +27,14 @@ from test_framework.psbt import (
     PSBT_GLOBAL_UNSIGNED_TX,
     PSBT_IN_RIPEMD160,
     PSBT_IN_SHA256,
+    PSBT_IN_SIGHASH_TYPE,
     PSBT_IN_HASH160,
     PSBT_IN_HASH256,
     PSBT_IN_NON_WITNESS_UTXO,
     PSBT_IN_WITNESS_UTXO,
     PSBT_OUT_TAP_TREE,
 )
-from test_framework.script import CScript, OP_TRUE
+from test_framework.script import CScript, OP_TRUE, SIGHASH_ALL, SIGHASH_ANYONECANPAY
 from test_framework.script_util import MIN_STANDARD_TX_NONWITNESS_SIZE
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import (
@@ -201,6 +202,100 @@ class PSBTTest(BitcoinTestFramework):
 
         wallet.unloadwallet()
 
+    def test_sighash_mismatch(self):
+        self.log.info("Test sighash type mismatches")
+        self.nodes[0].createwallet("sighash_mismatch")
+        wallet = self.nodes[0].get_wallet_rpc("sighash_mismatch")
+        def_wallet = self.nodes[0].get_wallet_rpc(self.default_wallet_name)
+
+        addr = wallet.getnewaddress(address_type="bech32")
+        def_wallet.sendtoaddress(addr, 5)
+        self.generate(self.nodes[0], 6)
+
+        # Retrieve the descriptors so we can do all of the tests with descriptorprocesspsbt as well
+        if self.options.descriptors:
+            descs = wallet.listdescriptors(True)["descriptors"]
+        else:
+            descs = [descsum_create(f"wpkh({wallet.dumpprivkey(addr)})")]
+
+        # Make a PSBT
+        psbt = wallet.walletcreatefundedpsbt([], [{def_wallet.getnewaddress(): 1}])["psbt"]
+
+        # Modify the PSBT and insert a sighash field for ALL|ANYONECANPAY on input 0
+        mod_psbt = PSBT.from_base64(psbt)
+        mod_psbt.i[0].map[PSBT_IN_SIGHASH_TYPE] = (SIGHASH_ALL | SIGHASH_ANYONECANPAY).to_bytes(4, byteorder="little")
+        psbt = mod_psbt.to_base64()
+
+        # Mismatching sighash type fails, including when no type is specified
+        for sighash in ["DEFAULT", "ALL", "NONE", "SINGLE", "NONE|ANYONECANPAY", "SINGLE|ANYONECANPAY", None]:
+            assert_raises_rpc_error(-22, "Specified sighash value does not match value stored in PSBT", wallet.walletprocesspsbt, psbt, True, sighash)
+
+        # Matching sighash type succeeds
+        proc = wallet.walletprocesspsbt(psbt, True, "ALL|ANYONECANPAY")
+        assert_equal(proc["complete"], True)
+
+        # Repeat with descriptorprocesspsbt
+        # Mismatching sighash type fails, including when no type is specified
+        for sighash in ["DEFAULT", "ALL", "NONE", "SINGLE", "NONE|ANYONECANPAY", "SINGLE|ANYONECANPAY", None]:
+            assert_raises_rpc_error(-22, "Specified sighash value does not match value stored in PSBT", self.nodes[0].descriptorprocesspsbt, psbt, descs, sighash)
+
+        # Matching sighash type succeeds
+        proc = self.nodes[0].descriptorprocesspsbt(psbt, descs, "ALL|ANYONECANPAY")
+        assert_equal(proc["complete"], True)
+
+        wallet.unloadwallet()
+
+    def test_sighash_adding(self):
+        self.log.info("Test adding of sighash type field")
+        self.nodes[0].createwallet("sighash_adding")
+        wallet = self.nodes[0].get_wallet_rpc("sighash_adding")
+        def_wallet = self.nodes[0].get_wallet_rpc(self.default_wallet_name)
+
+        addr = wallet.getnewaddress(address_type="bech32")
+        outputs = [{addr: 1}]
+        if self.options.descriptors:
+            outputs.append({wallet.getnewaddress(address_type="bech32m"): 1})
+            descs = wallet.listdescriptors(True)["descriptors"]
+        else:
+            descs = [descsum_create(f"wpkh({wallet.dumpprivkey(addr)})")]
+        def_wallet.send(outputs)
+        self.generate(self.nodes[0], 6)
+        utxos = wallet.listunspent()
+
+        # Make a PSBT
+        psbt = wallet.walletcreatefundedpsbt(utxos, [{def_wallet.getnewaddress(): 0.5}])["psbt"]
+
+        # Process the PSBT with the wallet
+        wallet_psbt = wallet.walletprocesspsbt(psbt=psbt, sighashtype="ALL|ANYONECANPAY", finalize=False)["psbt"]
+
+        # Separately process the PSBT with descriptors
+        desc_psbt = self.nodes[0].descriptorprocesspsbt(psbt=psbt, descriptors=descs, sighashtype="ALL|ANYONECANPAY", finalize=False)["psbt"]
+
+        for psbt in [wallet_psbt, desc_psbt]:
+            # Check that the PSBT has a sighash field on all inputs
+            dec_psbt = self.nodes[0].decodepsbt(psbt)
+            for input in dec_psbt["inputs"]:
+                assert_equal(input["sighash"], "ALL|ANYONECANPAY")
+
+            # Make sure we can still finalize the transaction
+            fin_res = self.nodes[0].finalizepsbt(psbt)
+            assert_equal(fin_res["complete"], True)
+            fin_hex = fin_res["hex"]
+
+            # Change the sighash field to a different value and make sure we can no longer finalize
+            mod_psbt = PSBT.from_base64(psbt)
+            mod_psbt.i[0].map[PSBT_IN_SIGHASH_TYPE] = (SIGHASH_ALL).to_bytes(4, byteorder="little")
+            if self.options.descriptors:
+                mod_psbt.i[1].map[PSBT_IN_SIGHASH_TYPE] = (SIGHASH_ALL).to_bytes(4, byteorder="little")
+            psbt = mod_psbt.to_base64()
+            fin_res = self.nodes[0].finalizepsbt(psbt)
+            assert_equal(fin_res["complete"], False)
+
+        self.nodes[0].sendrawtransaction(fin_hex)
+        self.generate(self.nodes[0], 1)
+
+        wallet.unloadwallet()
+
     def assert_change_type(self, psbtx, expected_type):
         """Assert that the given PSBT has a change output with the given type."""
 
@@ -1051,6 +1146,8 @@ class PSBTTest(BitcoinTestFramework):
         self.log.info("Test descriptorprocesspsbt raises if an invalid sighashtype is passed")
         assert_raises_rpc_error(-8, "'all' is not a valid sighash parameter.", self.nodes[2].descriptorprocesspsbt, psbt, [descriptor], sighashtype="all")
 
+        self.test_sighash_mismatch()
+        self.test_sighash_adding()
 
 if __name__ == '__main__':
     PSBTTest(__file__).main()