diff --git a/test/functional/mempool_truc.py b/test/functional/mempool_truc.py
index a7b5e83e89921..54a258215dc51 100755
--- a/test/functional/mempool_truc.py
+++ b/test/functional/mempool_truc.py
@@ -22,6 +22,7 @@
 
 MAX_REPLACEMENT_CANDIDATES = 100
 TRUC_MAX_VSIZE = 10000
+TRUC_CHILD_MAX_VSIZE = 1000
 
 def cleanup(extra_args=None):
     def decorator(func):
@@ -72,10 +73,10 @@ def test_truc_acceptance(self):
         self.check_mempool([tx_v3_parent_normal["txid"]])
         tx_v3_child_heavy = self.wallet.create_self_transfer(
             utxo_to_spend=tx_v3_parent_normal["new_utxo"],
-            target_vsize=1001,
+            target_vsize=TRUC_CHILD_MAX_VSIZE + 1,
             version=3
         )
-        assert_greater_than_or_equal(tx_v3_child_heavy["tx"].get_vsize(), 1000)
+        assert_greater_than_or_equal(tx_v3_child_heavy["tx"].get_vsize(), TRUC_CHILD_MAX_VSIZE)
         expected_error_child_heavy = f"TRUC-violation, version=3 child tx {tx_v3_child_heavy['txid']} (wtxid={tx_v3_child_heavy['wtxid']}) is too big"
         assert_raises_rpc_error(-26, expected_error_child_heavy, node.sendrawtransaction, tx_v3_child_heavy["hex"])
         self.check_mempool([tx_v3_parent_normal["txid"]])
@@ -87,10 +88,10 @@ def test_truc_acceptance(self):
             from_node=node,
             fee_rate=DEFAULT_FEE,
             utxo_to_spend=tx_v3_parent_normal["new_utxo"],
-            target_vsize=997,
+            target_vsize=TRUC_CHILD_MAX_VSIZE - 3,
             version=3
         )
-        assert_greater_than_or_equal(1000, tx_v3_child_almost_heavy["tx"].get_vsize())
+        assert_greater_than_or_equal(TRUC_CHILD_MAX_VSIZE, tx_v3_child_almost_heavy["tx"].get_vsize())
         self.check_mempool([tx_v3_parent_normal["txid"], tx_v3_child_almost_heavy["txid"]])
         assert_equal(node.getmempoolentry(tx_v3_parent_normal["txid"])["descendantcount"], 2)
         tx_v3_child_almost_heavy_rbf = self.wallet.send_self_transfer(
@@ -100,7 +101,8 @@ def test_truc_acceptance(self):
             target_vsize=875,
             version=3
         )
-        assert_greater_than_or_equal(tx_v3_child_almost_heavy["tx"].get_vsize() + tx_v3_child_almost_heavy_rbf["tx"].get_vsize(), 1000)
+        assert_greater_than_or_equal(tx_v3_child_almost_heavy["tx"].get_vsize() + tx_v3_child_almost_heavy_rbf["tx"].get_vsize(),
+                                     TRUC_CHILD_MAX_VSIZE)
         self.check_mempool([tx_v3_parent_normal["txid"], tx_v3_child_almost_heavy_rbf["txid"]])
         assert_equal(node.getmempoolentry(tx_v3_parent_normal["txid"])["descendantcount"], 2)
 
@@ -199,7 +201,7 @@ def test_truc_reorg(self):
         tx_v2_from_v3 = self.wallet.send_self_transfer(from_node=node, utxo_to_spend=tx_v3_block["new_utxo"], version=2)
         tx_v3_from_v2 = self.wallet.send_self_transfer(from_node=node, utxo_to_spend=tx_v2_block["new_utxo"], version=3)
         tx_v3_child_large = self.wallet.send_self_transfer(from_node=node, utxo_to_spend=tx_v3_block2["new_utxo"], target_vsize=1250, version=3)
-        assert_greater_than(node.getmempoolentry(tx_v3_child_large["txid"])["vsize"], 1000)
+        assert_greater_than(node.getmempoolentry(tx_v3_child_large["txid"])["vsize"], TRUC_CHILD_MAX_VSIZE)
         self.check_mempool([tx_v2_from_v3["txid"], tx_v3_from_v2["txid"], tx_v3_child_large["txid"]])
         node.invalidateblock(block[0])
         self.check_mempool([tx_v3_block["txid"], tx_v2_block["txid"], tx_v3_block2["txid"], tx_v2_from_v3["txid"], tx_v3_from_v2["txid"], tx_v3_child_large["txid"]])
@@ -231,7 +233,7 @@ def test_nondefault_package_limits(self):
 
         # Parent and child are within v3 limits, but parent's 10kvB descendant limit is exceeded
         assert_greater_than_or_equal(TRUC_MAX_VSIZE, tx_v3_parent_large1["tx"].get_vsize())
-        assert_greater_than_or_equal(1000, tx_v3_child_large1["tx"].get_vsize())
+        assert_greater_than_or_equal(TRUC_CHILD_MAX_VSIZE, tx_v3_child_large1["tx"].get_vsize())
         assert_greater_than(tx_v3_parent_large1["tx"].get_vsize() + tx_v3_child_large1["tx"].get_vsize(), 10000)
 
         assert_raises_rpc_error(-26, f"too-long-mempool-chain, exceeds descendant size limit for tx {tx_v3_parent_large1['txid']}", node.sendrawtransaction, tx_v3_child_large1["hex"])
@@ -254,7 +256,7 @@ def test_nondefault_package_limits(self):
 
         # Parent and child are within TRUC limits
         assert_greater_than_or_equal(TRUC_MAX_VSIZE, tx_v3_parent_large2["tx"].get_vsize())
-        assert_greater_than_or_equal(1000, tx_v3_child_large2["tx"].get_vsize())
+        assert_greater_than_or_equal(TRUC_CHILD_MAX_VSIZE, tx_v3_child_large2["tx"].get_vsize())
         assert_greater_than(tx_v3_parent_large2["tx"].get_vsize() + tx_v3_child_large2["tx"].get_vsize(), 10000)
 
         assert_raises_rpc_error(-26, f"too-long-mempool-chain, exceeds ancestor size limit", node.sendrawtransaction, tx_v3_child_large2["hex"])
@@ -281,7 +283,7 @@ def test_truc_ancestors_package(self):
         )
         tx_v3_child_heavy = self.wallet.create_self_transfer_multi(
             utxos_to_spend=[tx_v3_parent_normal["new_utxo"]],
-            target_vsize=1001,
+            target_vsize=TRUC_CHILD_MAX_VSIZE + 1,
             fee_per_output=10000,
             version=3
         )