diff --git a/test/functional/mempool_reorg.py b/test/functional/mempool_reorg.py
--- a/test/functional/mempool_reorg.py
+++ b/test/functional/mempool_reorg.py
@@ -9,7 +9,8 @@
 """
 
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import assert_equal, assert_raises_rpc_error, create_tx
+from test_framework.blocktools import create_raw_transaction
+from test_framework.util import assert_equal, assert_raises_rpc_error
 
 # Create one-input, one-output, no-fee transaction:
 
@@ -41,11 +42,11 @@
         # and make sure the mempool code behaves correctly.
         b = [self.nodes[0].getblockhash(n) for n in range(101, 105)]
         coinbase_txids = [self.nodes[0].getblock(h)['tx'][0] for h in b]
-        spend_101_raw = create_tx(
+        spend_101_raw = create_raw_transaction(
             self.nodes[0], coinbase_txids[1], node1_address, 49.99)
-        spend_102_raw = create_tx(
+        spend_102_raw = create_raw_transaction(
             self.nodes[0], coinbase_txids[2], node0_address, 49.99)
-        spend_103_raw = create_tx(
+        spend_103_raw = create_raw_transaction(
             self.nodes[0], coinbase_txids[3], node0_address, 49.99)
 
         # Create a transaction which is time-locked to two blocks in the future
@@ -70,9 +71,9 @@
                                 self.nodes[0].sendrawtransaction, timelock_tx)
 
         # Create 102_1 and 103_1:
-        spend_102_1_raw = create_tx(
+        spend_102_1_raw = create_raw_transaction(
             self.nodes[0], spend_102_id, node1_address, 49.98)
-        spend_103_1_raw = create_tx(
+        spend_103_1_raw = create_raw_transaction(
             self.nodes[0], spend_103_id, node1_address, 49.98)
 
         # Broadcast and mine 103_1:
diff --git a/test/functional/mempool_resurrect.py b/test/functional/mempool_resurrect.py
--- a/test/functional/mempool_resurrect.py
+++ b/test/functional/mempool_resurrect.py
@@ -5,7 +5,8 @@
 """Test resurrection of mined transactions when the blockchain is re-organized."""
 
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import assert_equal, create_tx
+from test_framework.blocktools import create_raw_transaction
+from test_framework.util import assert_equal
 
 # Create one-input, one-output, no-fee transaction:
 
@@ -29,7 +30,7 @@
 
         b = [self.nodes[0].getblockhash(n) for n in range(1, 4)]
         coinbase_txids = [self.nodes[0].getblock(h)['tx'][0] for h in b]
-        spends1_raw = [create_tx(self.nodes[0], txid, node0_address, 49.99)
+        spends1_raw = [create_raw_transaction(self.nodes[0], txid, node0_address, 49.99)
                        for txid in coinbase_txids]
         spends1_id = [self.nodes[0].sendrawtransaction(tx)
                       for tx in spends1_raw]
@@ -37,7 +38,7 @@
         blocks = []
         blocks.extend(self.nodes[0].generate(1))
 
-        spends2_raw = [create_tx(self.nodes[0], txid, node0_address, 49.98)
+        spends2_raw = [create_raw_transaction(self.nodes[0], txid, node0_address, 49.98)
                        for txid in spends1_id]
         spends2_id = [self.nodes[0].sendrawtransaction(tx)
                       for tx in spends2_raw]
diff --git a/test/functional/mempool_spend_coinbase.py b/test/functional/mempool_spend_coinbase.py
--- a/test/functional/mempool_spend_coinbase.py
+++ b/test/functional/mempool_spend_coinbase.py
@@ -13,7 +13,9 @@
 """
 
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import assert_equal, assert_raises_rpc_error, create_tx
+from test_framework.blocktools import create_raw_transaction
+from test_framework.util import assert_equal, assert_raises_rpc_error
+
 # Create one-input, one-output, no-fee transaction:
 
 
@@ -32,7 +34,7 @@
         # is too immature to spend.
         b = [self.nodes[0].getblockhash(n) for n in range(101, 103)]
         coinbase_txids = [self.nodes[0].getblock(h)['tx'][0] for h in b]
-        spends_raw = [create_tx(self.nodes[0], txid, node0_address, 49.99)
+        spends_raw = [create_raw_transaction(self.nodes[0], txid, node0_address, 49.99)
                       for txid in coinbase_txids]
 
         spend_101_id = self.nodes[0].sendrawtransaction(spends_raw[0])
diff --git a/test/functional/test_framework/blocktools.py b/test/functional/test_framework/blocktools.py
--- a/test/functional/test_framework/blocktools.py
+++ b/test/functional/test_framework/blocktools.py
@@ -25,7 +25,7 @@
     ser_string,
 )
 from .txtools import pad_tx
-from .util import satoshi_round
+from .util import assert_equal, satoshi_round
 
 # Create a block (with regtest difficulty)
 
@@ -106,6 +106,20 @@
     return tx
 
 
+def create_raw_transaction(node, txid, to_address, amount):
+    """ Return raw signed transaction spending the first output of the
+        input txid. Note that the node must be able to sign for the
+        output that is being spent, and the node must not be running
+        multiple wallets.
+    """
+    inputs = [{"txid": txid, "vout": 0}]
+    outputs = {to_address: amount}
+    rawtx = node.createrawtransaction(inputs, outputs)
+    signresult = node.signrawtransactionwithwallet(rawtx)
+    assert_equal(signresult["complete"], True)
+    return signresult['hex']
+
+
 def get_legacy_sigopcount_block(block, fAccurate=True):
     count = 0
     for tx in block.vtx:
diff --git a/test/functional/test_framework/util.py b/test/functional/test_framework/util.py
--- a/test/functional/test_framework/util.py
+++ b/test/functional/test_framework/util.py
@@ -555,15 +555,6 @@
         txouts = txouts + script_pubkey
     return txouts
 
-
-def create_tx(node, coinbase, to_address, amount):
-    inputs = [{"txid": coinbase, "vout": 0}]
-    outputs = {to_address: amount}
-    rawtx = node.createrawtransaction(inputs, outputs)
-    signresult = node.signrawtransactionwithwallet(rawtx)
-    assert_equal(signresult["complete"], True)
-    return signresult["hex"]
-
 # Create a spend of each passed-in utxo, splicing in "txouts" to each raw
 # transaction to make it large.  See gen_return_txouts() above.