diff --git a/atst/routes/task_orders/index.py b/atst/routes/task_orders/index.py
index 6a632cbb..6abf34fd 100644
--- a/atst/routes/task_orders/index.py
+++ b/atst/routes/task_orders/index.py
@@ -3,6 +3,7 @@ from flask import g, Response, current_app as app
 
 from . import task_orders_bp
 from atst.domain.task_orders import TaskOrders
+from atst.domain.exceptions import NotFoundError
 from atst.utils.docx import Docx
 
 
diff --git a/tests/routes/task_orders/test_index.py b/tests/routes/task_orders/test_index.py
index 9ca5ea64..45db3a82 100644
--- a/tests/routes/task_orders/test_index.py
+++ b/tests/routes/task_orders/test_index.py
@@ -28,3 +28,46 @@ def test_download_summary(client, user_session):
     for attr, val in task_order.to_dictionary().items():
         assert attr in doc
         assert xml_translated(val) in doc
+
+
+class TestDownloadCSPEstimate:
+    def setup(self):
+        self.user = UserFactory.create()
+        self.portfolio = PortfolioFactory.create(owner=self.user)
+        self.task_order = TaskOrderFactory.create(
+            creator=self.user, portfolio=self.portfolio
+        )
+
+    def test_successful_download(self, client, user_session, pdf_upload):
+        self.task_order.csp_estimate = pdf_upload
+        user_session(self.user)
+        response = client.get(
+            url_for(
+                "task_orders.download_csp_estimate", task_order_id=self.task_order.id
+            )
+        )
+        assert response.status_code == 200
+
+        pdf_upload.seek(0)
+        expected_contents = pdf_upload.read()
+        assert expected_contents == response.data
+
+    def test_download_without_attachment(self, client, user_session):
+        self.task_order.attachment_id = None
+        user_session(self.user)
+        response = client.get(
+            url_for(
+                "task_orders.download_csp_estimate", task_order_id=self.task_order.id
+            )
+        )
+        assert response.status_code == 404
+
+    def test_download_with_wrong_user(self, client, user_session):
+        other_user = UserFactory.create()
+        user_session(other_user)
+        response = client.get(
+            url_for(
+                "task_orders.download_csp_estimate", task_order_id=self.task_order.id
+            )
+        )
+        assert response.status_code == 404