diff --git a/lago_python_client/models/customer_usage.py b/lago_python_client/models/customer_usage.py
index 78bf752..cfb01a3 100644
--- a/lago_python_client/models/customer_usage.py
+++ b/lago_python_client/models/customer_usage.py
@@ -73,7 +73,7 @@ class CustomerUsageResponse(BaseResponseModel):
     from_datetime: str
     to_datetime: str
     issuing_date: str
-    invoice_id: Optional[str]
+    lago_invoice_id: Optional[str]
     currency: str
     amount_cents: int
     total_amount_cents: int
diff --git a/tests/fixtures/customer_usage.json b/tests/fixtures/customer_usage.json
index a0ad50d..885b2fa 100644
--- a/tests/fixtures/customer_usage.json
+++ b/tests/fixtures/customer_usage.json
@@ -3,7 +3,7 @@
     "from_datetime": "2022-07-01T00:00:00Z",
     "to_datetime": "2022-07-31T23:59:59Z",
     "issuing_date": "2022-08-01",
-    "invoice_id": null,
+    "lago_invoice_id": null,
     "currency": "EUR",
     "amount_cents": 123,
     "total_amount_cents": 123,
diff --git a/tests/test_customer_client.py b/tests/test_customer_client.py
index 4ce3564..9c7ed58 100644
--- a/tests/test_customer_client.py
+++ b/tests/test_customer_client.py
@@ -130,6 +130,7 @@ def test_valid_current_usage(httpx_mock: HTTPXMock):
     response = client.customers.current_usage("external_customer_id", "123")
 
     assert response.from_datetime == "2022-07-01T00:00:00Z"
+    assert response.lago_invoice_id is None
     assert len(response.charges_usage) == 1
     assert response.charges_usage[0].units == "1.0"
     assert len(response.charges_usage[0].filters) == 1
@@ -272,6 +273,7 @@ def test_valid_past_usage(httpx_mock: HTTPXMock):
 
     assert len(response["usage_periods"]) == 1
     assert response["usage_periods"][0].from_datetime == "2022-07-01T00:00:00Z"
+    assert response["usage_periods"][0].lago_invoice_id == "1a901a90-1a90-1a90-1a90-1a901a901a90"
     assert len(response["usage_periods"][0].charges_usage) == 1
     assert response["usage_periods"][0].charges_usage[0].units == "1.0"
     assert len(response["usage_periods"][0].charges_usage[0].filters) == 1