diff --git a/chia/_tests/core/full_node/test_full_node.py b/chia/_tests/core/full_node/test_full_node.py
index 2f4cafbf1e0f..8a23b19565a7 100644
--- a/chia/_tests/core/full_node/test_full_node.py
+++ b/chia/_tests/core/full_node/test_full_node.py
@@ -935,8 +935,8 @@ async def test_new_transaction_and_mempool(self, wallet_nodes, self_hostname, se
         # these numbers reflect the capacity of the mempool. In these
         # tests MEMPOOL_BLOCK_BUFFER is 1. The other factors are COST_PER_BYTE
         # and MAX_BLOCK_COST_CLVM
-        assert included_tx == 23
-        assert not_included_tx == 10
+        assert included_tx == 27
+        assert not_included_tx == 6
         assert seen_bigger_transaction_has_high_fee
 
         # Mempool is full
diff --git a/chia/full_node/mempool_manager.py b/chia/full_node/mempool_manager.py
index 6d49674f6c08..afc48de758aa 100644
--- a/chia/full_node/mempool_manager.py
+++ b/chia/full_node/mempool_manager.py
@@ -302,7 +302,9 @@ async def pre_validate_spendbundle(
         if ret.error is not None:
             raise ValidationError(Err(ret.error), "pre_validate_spendbundle failed")
         assert ret.conds is not None
-        return ret.conds
+        # TODO: this cost padding is temporary, until we update the mempool's
+        # block creation logic to take the block overhead into account
+        return ret.conds.replace(cost=ret.conds.cost + 10000000)
 
     async def add_spend_bundle(
         self,