diff --git a/ag_bids_mcp/client.py b/ag_bids_mcp/client.py
index e09053d..884cdec 100644
--- a/ag_bids_mcp/client.py
+++ b/ag_bids_mcp/client.py
@@ -56,10 +56,14 @@ def _get(path: str, **params: Any) -> dict | list:
 def latest(commodity: str | None = None, source: str | None = None,
            delivery: str | None = None, kind: str | None = None,
            zip: str | None = None, lat: float | None = None,
-           lng: float | None = None, radius_miles: float | None = None) -> dict:
+           lng: float | None = None, radius_miles: float | None = None,
+           include_expired: bool = False) -> dict:
+    # Only send include_expired when True — _get drops None, so the default
+    # call keeps its existing query string (current + future months only).
     return _get("/api/data/latest",
                 commodity=commodity, source=source, delivery=delivery, kind=kind,
-                zip=zip, lat=lat, lng=lng, radius_miles=radius_miles)
+                zip=zip, lat=lat, lng=lng, radius_miles=radius_miles,
+                include_expired=True if include_expired else None)
 
 
 def history(commodity: str | None = None, source_id: int | None = None,
diff --git a/ag_bids_mcp/server.py b/ag_bids_mcp/server.py
index 0f435df..cb15794 100644
--- a/ag_bids_mcp/server.py
+++ b/ag_bids_mcp/server.py
@@ -176,13 +176,22 @@ def latest_prices(
         Field(description="Search radius in miles around the location (default 50). "
                           "Ignored unless a ZIP or lat/lng is given."),
     ] = None,
+    include_expired: Annotated[
+        bool,
+        Field(description="Include past/expired delivery months. Default off — only "
+                          "the current and future months are shown. Set true only when "
+                          "the farmer explicitly asks for historical/past delivery data."),
+    ] = False,
 ) -> str:
     """Snapshot of the latest scraped bid per (source, commodity, delivery).
 
     Every filter is optional and AND'd together — pivot by elevator, crop,
     delivery, or kind in any combination. Pass a `zip` (or `lat`+`lng`) with
     optional `radius_miles` to keep only elevators near the farmer, sorted
-    nearest-first with the distance shown."""
+    nearest-first with the distance shown.
+
+    By default this shows current + future delivery months only; expired
+    months are rolled off. Set `include_expired=true` for a historical view."""
     cm = commodity.strip().lower() if commodity else None
     with track("latest_prices", commodity=cm, source=source, delivery=delivery, kind=kind,
                zip=zip or "", radius=radius_miles or 0):
@@ -190,7 +199,8 @@ def latest_prices(
         if err:
             return err
         payload = client.latest(commodity=cm, source=source, delivery=delivery, kind=kind,
-                                zip=zip, lat=lat, lng=lng, radius_miles=radius_miles)
+                                zip=zip, lat=lat, lng=lng, radius_miles=radius_miles,
+                                include_expired=include_expired)
         return fmt.fmt_latest(payload)
 
 
diff --git a/tests/test_client.py b/tests/test_client.py
index 3c6a0fd..bdc5542 100644
--- a/tests/test_client.py
+++ b/tests/test_client.py
@@ -71,6 +71,30 @@ def test_get_drops_none_params(monkeypatch):
     assert captured["params"] == {"commodity": "corn"}
 
 
+def test_latest_include_expired_passthrough(monkeypatch):
+    client = _reload_client(monkeypatch)
+    captured = {}
+
+    class FakeResp:
+        status_code = 200
+        text = ""
+        def json(self): return {"count": 0, "rows": []}
+
+    def fake_get(url, params=None, timeout=None, headers=None):
+        captured["params"] = dict(params or {})
+        return FakeResp()
+
+    monkeypatch.setattr(client.httpx, "get", fake_get)
+
+    # Default: not sent, so the API applies its current+future filter.
+    client.latest(commodity="corn")
+    assert "include_expired" not in captured["params"]
+
+    # Opt in: forwarded so the API returns expired months too.
+    client.latest(commodity="corn", include_expired=True)
+    assert captured["params"] == {"commodity": "corn", "include_expired": True}
+
+
 def test_futures_endpoint_params(monkeypatch):
     client = _reload_client(monkeypatch)
     captured = {}