diff --git a/qiskit/extensions/hamiltonian_gate.py b/qiskit/extensions/hamiltonian_gate.py
index b35c09ca4ece..81730ef15d4a 100644
--- a/qiskit/extensions/hamiltonian_gate.py
+++ b/qiskit/extensions/hamiltonian_gate.py
@@ -134,4 +134,4 @@ def hamiltonian(self, operator, time, qubits, label=None):
     return self.append(HamiltonianGate(data=operator, time=time, label=label), qubits, [])
 
 
-QuantumCircuit.hamiltonian = hamiltonian
+QuantumCircuit.hamiltonian = hamiltonian  # type: ignore[attr-defined]
diff --git a/qiskit/extensions/quantum_initializer/diagonal.py b/qiskit/extensions/quantum_initializer/diagonal.py
index b4c24fc41b61..69c9a0f42588 100644
--- a/qiskit/extensions/quantum_initializer/diagonal.py
+++ b/qiskit/extensions/quantum_initializer/diagonal.py
@@ -154,4 +154,4 @@ def diagonal(self, diag, qubit):
     return self.append(DiagonalGate(diag), qubit)
 
 
-QuantumCircuit.diagonal = diagonal
+QuantumCircuit.diagonal = diagonal  # type: ignore[attr-defined]
diff --git a/qiskit/extensions/quantum_initializer/initializer.py b/qiskit/extensions/quantum_initializer/initializer.py
index 8382fa62f846..700734bf153f 100644
--- a/qiskit/extensions/quantum_initializer/initializer.py
+++ b/qiskit/extensions/quantum_initializer/initializer.py
@@ -188,4 +188,4 @@ class to prepare the qubits in a specified state.
     return self.append(Initialize(params, num_qubits), qubits)
 
 
-QuantumCircuit.initialize = initialize
+QuantumCircuit.initialize = initialize  # type: ignore[attr-defined]
diff --git a/qiskit/extensions/quantum_initializer/isometry.py b/qiskit/extensions/quantum_initializer/isometry.py
index cb3bb1f12311..1dc1acb886ff 100644
--- a/qiskit/extensions/quantum_initializer/isometry.py
+++ b/qiskit/extensions/quantum_initializer/isometry.py
@@ -611,5 +611,5 @@ def iso(
 
 
 # support both QuantumCircuit.iso and QuantumCircuit.isometry
-QuantumCircuit.iso = iso
-QuantumCircuit.isometry = iso
+QuantumCircuit.iso = iso  # type: ignore[attr-defined]
+QuantumCircuit.isometry = iso  # type: ignore[attr-defined]
diff --git a/qiskit/extensions/quantum_initializer/squ.py b/qiskit/extensions/quantum_initializer/squ.py
index 480f6443d5c4..3543ece6c49b 100644
--- a/qiskit/extensions/quantum_initializer/squ.py
+++ b/qiskit/extensions/quantum_initializer/squ.py
@@ -201,4 +201,4 @@ def squ(
     return self.append(SingleQubitUnitary(unitary_matrix, mode, up_to_diagonal), [qubit], [])
 
 
-QuantumCircuit.squ = squ
+QuantumCircuit.squ = squ  # type: ignore[attr-defined]
diff --git a/qiskit/extensions/quantum_initializer/uc.py b/qiskit/extensions/quantum_initializer/uc.py
index f432a7ebd082..074a48b155e7 100644
--- a/qiskit/extensions/quantum_initializer/uc.py
+++ b/qiskit/extensions/quantum_initializer/uc.py
@@ -350,4 +350,4 @@ def uc(self, gate_list, q_controls, q_target, up_to_diagonal=False):
     return self.append(UCGate(gate_list, up_to_diagonal), [q_target] + q_controls)
 
 
-QuantumCircuit.uc = uc
+QuantumCircuit.uc = uc  # type: ignore[attr-defined]
diff --git a/qiskit/extensions/quantum_initializer/ucrx.py b/qiskit/extensions/quantum_initializer/ucrx.py
index 5d412f1e0bc8..3e91b125beaa 100644
--- a/qiskit/extensions/quantum_initializer/ucrx.py
+++ b/qiskit/extensions/quantum_initializer/ucrx.py
@@ -94,4 +94,4 @@ def ucrx(self, angle_list, q_controls, q_target):
     return self.append(UCRXGate(angle_list), [q_target] + q_controls, [])
 
 
-QuantumCircuit.ucrx = ucrx
+QuantumCircuit.ucrx = ucrx  # type: ignore[attr-defined]
diff --git a/qiskit/extensions/quantum_initializer/ucry.py b/qiskit/extensions/quantum_initializer/ucry.py
index b8642bac0cc7..5b5c81b5813c 100644
--- a/qiskit/extensions/quantum_initializer/ucry.py
+++ b/qiskit/extensions/quantum_initializer/ucry.py
@@ -91,4 +91,4 @@ def ucry(self, angle_list, q_controls, q_target):
     return self.append(UCRYGate(angle_list), [q_target] + q_controls, [])
 
 
-QuantumCircuit.ucry = ucry
+QuantumCircuit.ucry = ucry  # type: ignore[attr-defined]
diff --git a/qiskit/extensions/quantum_initializer/ucrz.py b/qiskit/extensions/quantum_initializer/ucrz.py
index 7cead50c79ce..83be9257a80e 100644
--- a/qiskit/extensions/quantum_initializer/ucrz.py
+++ b/qiskit/extensions/quantum_initializer/ucrz.py
@@ -92,4 +92,4 @@ def ucrz(self, angle_list, q_controls, q_target):
     return self.append(UCRZGate(angle_list), [q_target] + q_controls, [])
 
 
-QuantumCircuit.ucrz = ucrz
+QuantumCircuit.ucrz = ucrz  # type: ignore[attr-defined]
diff --git a/qiskit/extensions/simulator/snapshot.py b/qiskit/extensions/simulator/snapshot.py
index a5806da879e8..8cf5893e1c00 100644
--- a/qiskit/extensions/simulator/snapshot.py
+++ b/qiskit/extensions/simulator/snapshot.py
@@ -126,4 +126,4 @@ def snapshot(self, label, snapshot_type="statevector", qubits=None, params=None)
 
 
 # Add to QuantumCircuit class
-QuantumCircuit.snapshot = snapshot
+QuantumCircuit.snapshot = snapshot  # type: ignore[attr-defined]
diff --git a/qiskit/extensions/unitary.py b/qiskit/extensions/unitary.py
index 5d9364805ded..97e42da96839 100644
--- a/qiskit/extensions/unitary.py
+++ b/qiskit/extensions/unitary.py
@@ -251,4 +251,4 @@ def unitary(self, obj, qubits, label=None):
     return self.append(gate, qubits, [])
 
 
-QuantumCircuit.unitary = unitary
+QuantumCircuit.unitary = unitary  # type: ignore[attr-defined]