diff --git a/src/api/connectors.py b/src/api/connectors.py
index 87bc740da..e6ba01336 100644
--- a/src/api/connectors.py
+++ b/src/api/connectors.py
@@ -876,8 +876,8 @@ async def connector_sync(
             {
                 "task_ids": task_ids,
                 "status": "sync_started",
-                "message": f"Started syncing files from {len(active_connections)} {connector_type} connection(s)",
-                "connections_synced": len(active_connections),
+                "message": f"Started syncing files from 1 {connector_type} connection",
+                "connections_synced": len(task_ids),
             },
             status_code=201,
         )
diff --git a/tests/unit/api/test_connector_sync_response.py b/tests/unit/api/test_connector_sync_response.py
new file mode 100644
index 000000000..15608de48
--- /dev/null
+++ b/tests/unit/api/test_connector_sync_response.py
@@ -0,0 +1,110 @@
+"""Unit test for connector_sync response reporting (GitHub issue #1547).
+
+The success response must report exactly 1 connection synced and a singular message,
+even when multiple active connections exist, because the function dispatches exactly
+one task from exactly one working connection.
+"""
+
+import json
+import sys
+from pathlib import Path
+from types import SimpleNamespace
+from unittest.mock import AsyncMock, MagicMock
+
+import pytest
+
+ROOT = Path(__file__).resolve().parent.parent.parent.parent
+SRC = ROOT / "src"
+if str(SRC) not in sys.path:
+    sys.path.insert(0, str(SRC))
+
+
+def _make_connection(connection_id: str, is_active: bool = True):
+    return SimpleNamespace(connection_id=connection_id, is_active=is_active)
+
+
+def _json(response):
+    return json.loads(response.body.decode())
+
+
+@pytest.mark.asyncio
+async def test_connector_sync_reports_one_connection_with_multiple_active(monkeypatch):
+    """When multiple active connections exist, response should report 1 connection synced."""
+    from api import connectors as connectors_api
+
+    monkeypatch.setattr(connectors_api.TelemetryClient, "send_event", AsyncMock())
+    monkeypatch.setattr(
+        connectors_api,
+        "get_synced_file_ids_for_connector",
+        AsyncMock(return_value=(["file-a", "file-b"], [], "document_id")),
+    )
+    monkeypatch.setattr(
+        connectors_api,
+        "reconcile_orphans_for_connector_type",
+        AsyncMock(return_value=[]),
+    )
+
+    # Create THREE active connections to test the over-counting bug
+    conn1 = _make_connection("conn-1")
+    conn2 = _make_connection("conn-2")
+    conn3 = _make_connection("conn-3")
+
+    # First connector authenticates successfully (will be selected as working_connection)
+    connector1 = MagicMock()
+    connector1.authenticate = AsyncMock(return_value=True)
+
+    # Other connectors don't matter since first one succeeds
+    connector2 = MagicMock()
+    connector2.authenticate = AsyncMock(return_value=False)
+    connector3 = MagicMock()
+    connector3.authenticate = AsyncMock(return_value=False)
+
+    service = MagicMock()
+    service.connection_manager = MagicMock()
+    service.connection_manager.list_connections = AsyncMock(
+        return_value=[conn1, conn2, conn3]
+    )
+
+    async def _get_connector(connection_id):
+        return {
+            "conn-1": connector1,
+            "conn-2": connector2,
+            "conn-3": connector3,
+        }[connection_id]
+
+    service.get_connector = AsyncMock(side_effect=_get_connector)
+    service.sync_specific_files = AsyncMock(return_value="task-123")
+
+    response = await connectors_api.connector_sync(
+        "google_drive",
+        connectors_api.ConnectorSyncBody(),
+        request=MagicMock(),
+        connector_service=service,
+        session_manager=MagicMock(),
+        user=SimpleNamespace(user_id="alice", jwt_token="token"),
+        session=MagicMock(),
+    )
+
+    assert response.status_code == 201
+    body = _json(response)
+
+    # The fix: should report 1 connection synced, not 3
+    assert body["connections_synced"] == 1, (
+        f"Expected connections_synced=1 but got {body['connections_synced']}. "
+        "Only one connection is actually synced even when multiple are active."
+    )
+
+    # The fix: message should be singular, not plural
+    assert body["message"] == "Started syncing files from 1 google_drive connection", (
+        f"Expected singular message but got: {body['message']}"
+    )
+
+    # Verify exactly one task was dispatched
+    assert body["task_ids"] == ["task-123"]
+    assert len(body["task_ids"]) == 1
+
+    # Verify only the first connector was used
+    service.sync_specific_files.assert_awaited_once()
+    args = service.sync_specific_files.await_args.args
+    assert args[0] == "conn-1"  # connection_id of first connector
+