diff --git a/surfsense_backend/tests/conftest.py b/surfsense_backend/tests/conftest.py
index bfdb47a95..effde2714 100644
--- a/surfsense_backend/tests/conftest.py
+++ b/surfsense_backend/tests/conftest.py
@@ -14,6 +14,7 @@ from tests.utils.helpers import (
     delete_document,
     get_auth_token,
     get_search_space_id,
+    poll_document_status,
 )
 
 
@@ -40,6 +41,74 @@ async def search_space_id(backend_url: str, auth_token: str) -> int:
         return await get_search_space_id(client, auth_token)
 
 
+@pytest.fixture(scope="session", autouse=True)
+async def _purge_test_search_space(
+    backend_url: str,
+    auth_token: str,
+    search_space_id: int,
+):
+    """
+    Delete all documents in the test search space before the session starts.
+
+    Ensures no stale data from a previous run interferes with the current
+    session.  Paginates through all documents and waits for any in-flight
+    documents to reach a terminal state before deleting.
+    """
+    hdrs = auth_headers(auth_token)
+    async with httpx.AsyncClient(base_url=backend_url, timeout=60.0) as client:
+        all_docs: list[dict] = []
+        page = 0
+        page_size = 200
+
+        while True:
+            resp = await client.get(
+                "/api/v1/documents",
+                headers=hdrs,
+                params={
+                    "search_space_id": search_space_id,
+                    "page": page,
+                    "page_size": page_size,
+                },
+            )
+            if resp.status_code != 200:
+                break
+
+            body = resp.json()
+            all_docs.extend(body.get("items", []))
+
+            if not body.get("has_more", False):
+                break
+            page += 1
+
+        if not all_docs:
+            yield
+            return
+
+        in_flight = [
+            doc["id"]
+            for doc in all_docs
+            if doc.get("status", {}).get("state") in ("pending", "processing")
+        ]
+        if in_flight:
+            with contextlib.suppress(Exception):
+                await poll_document_status(
+                    client,
+                    hdrs,
+                    in_flight,
+                    search_space_id=search_space_id,
+                    timeout=120.0,
+                )
+
+        for doc in all_docs:
+            with contextlib.suppress(Exception):
+                await client.delete(
+                    f"/api/v1/documents/{doc['id']}",
+                    headers=hdrs,
+                )
+
+    yield
+
+
 @pytest.fixture(scope="session")
 def headers(auth_token: str) -> dict[str, str]:
     """Authorization headers reused across all tests in the session."""