diff --git a/crates/circuit/src/dag_circuit.rs b/crates/circuit/src/dag_circuit.rs
index d9425036b445..6851457d161c 100644
--- a/crates/circuit/src/dag_circuit.rs
+++ b/crates/circuit/src/dag_circuit.rs
@@ -6227,8 +6227,8 @@ impl DAGCircuit {
             unit: "dt".to_string(),
             qubit_locations: PyDict::new_bound(py).unbind(),
             clbit_locations: PyDict::new_bound(py).unbind(),
-            qubit_io_map: IndexMap::with_capacity_and_hasher(num_qubits, RandomState::new()),
-            clbit_io_map: IndexMap::with_capacity_and_hasher(num_clbits, RandomState::new()),
+            qubit_io_map: Vec::with_capacity(num_qubits),
+            clbit_io_map: Vec::with_capacity(num_clbits),
             var_input_map: _VarIndexMap::new(py),
             var_output_map: _VarIndexMap::new(py),
             op_names: IndexMap::default(),