diff --git a/electrum/commands.py b/electrum/commands.py
index cbeaf61c9..7b2a45d64 100644
--- a/electrum/commands.py
+++ b/electrum/commands.py
@@ -423,15 +423,27 @@ class Commands:
         return {'address':address, 'redeemScript':redeem_script}
 
     @command('w')
-    async def freeze(self, address, wallet: Abstract_Wallet = None):
+    async def freeze(self, address: str, wallet: Abstract_Wallet = None):
         """Freeze address. Freeze the funds at one of your wallet\'s addresses"""
         return wallet.set_frozen_state_of_addresses([address], True)
 
     @command('w')
-    async def unfreeze(self, address, wallet: Abstract_Wallet = None):
+    async def unfreeze(self, address: str, wallet: Abstract_Wallet = None):
         """Unfreeze address. Unfreeze the funds at one of your wallet\'s address"""
         return wallet.set_frozen_state_of_addresses([address], False)
 
+    @command('w')
+    async def freeze_utxo(self, coin: str, wallet: Abstract_Wallet = None):
+        """Freeze a UTXO so that the wallet will not spend it."""
+        wallet.set_frozen_state_of_coins([coin], True)
+        return True
+
+    @command('w')
+    async def unfreeze_utxo(self, coin: str, wallet: Abstract_Wallet = None):
+        """Unfreeze a UTXO so that the wallet might spend it."""
+        wallet.set_frozen_state_of_coins([coin], False)
+        return True
+
     @command('wp')
     async def getprivatekeys(self, address, password=None, wallet: Abstract_Wallet = None):
         """Get private keys of addresses. You may pass a single wallet address, or a list of wallet addresses."""
diff --git a/electrum/gui/qt/main_window.py b/electrum/gui/qt/main_window.py
index f0532f49c..3e36fe582 100644
--- a/electrum/gui/qt/main_window.py
+++ b/electrum/gui/qt/main_window.py
@@ -1953,7 +1953,8 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger):
         self.utxo_list.update()
 
     def set_frozen_state_of_coins(self, utxos: Sequence[PartialTxInput], freeze: bool):
-        self.wallet.set_frozen_state_of_coins(utxos, freeze)
+        utxos_str = {utxo.prevout.to_str() for utxo in utxos}
+        self.wallet.set_frozen_state_of_coins(utxos_str, freeze)
         self.utxo_list.update()
 
     def create_list_tab(self, l, toolbar=None):
diff --git a/electrum/transaction.py b/electrum/transaction.py
index ccb6305d0..d399cefdc 100644
--- a/electrum/transaction.py
+++ b/electrum/transaction.py
@@ -176,6 +176,7 @@ class TxOutpoint(NamedTuple):
     @classmethod
     def from_str(cls, s: str) -> 'TxOutpoint':
         hash_str, idx_str = s.split(':')
+        assert len(hash_str) == 64, f"{hash_str} should be a sha256 hash"
         return TxOutpoint(txid=bfh(hash_str),
                           out_idx=int(idx_str))
 
diff --git a/electrum/wallet.py b/electrum/wallet.py
index f853000b0..687775394 100644
--- a/electrum/wallet.py
+++ b/electrum/wallet.py
@@ -1337,9 +1337,10 @@ class Abstract_Wallet(AddressSynchronizer, ABC):
                 return True
         return False
 
-    def set_frozen_state_of_coins(self, utxos: Sequence[PartialTxInput], freeze: bool) -> None:
+    def set_frozen_state_of_coins(self, utxos: Sequence[str], freeze: bool) -> None:
         """Set frozen state of the utxos to FREEZE, True or False"""
-        utxos = {utxo.prevout.to_str() for utxo in utxos}
+        # basic sanity check that input is not garbage: (see if raises)
+        [TxOutpoint.from_str(utxo) for utxo in utxos]
         with self._freeze_lock:
             if freeze:
                 self._frozen_coins |= set(utxos)