diff --git a/buildbotapi.py b/buildbotapi.py
index c251f537..8529650c 100644
--- a/buildbotapi.py
+++ b/buildbotapi.py
@@ -1,4 +1,5 @@
 import json
+import time
 from dataclasses import dataclass
 from typing import Any, cast
 
@@ -6,6 +7,11 @@
 
 JSON = dict[str, Any]
 
+# Builders whose most recent build was more than this many days ago
+#  are considered inactive and ignored when checking for failures
+STALE_BUILDER_DAYS = 14
+SECONDS_PER_DAY = 24 * 60 * 60
+
 
 @dataclass
 class Builder:
@@ -66,6 +72,10 @@ async def is_builder_failing_currently(self, builder: Builder) -> bool:
         if not builds:
             return False
         (build,) = builds
+
+        age_days = (time.time() - build["complete_at"]) / SECONDS_PER_DAY
+        if age_days > STALE_BUILDER_DAYS:
+            return False
         if build["results"] == 2:
             return True
         return False
diff --git a/tests/test_buildbotapi.py b/tests/test_buildbotapi.py
index 0092505e..f45e2b56 100644
--- a/tests/test_buildbotapi.py
+++ b/tests/test_buildbotapi.py
@@ -108,17 +108,28 @@ async def test_buildbotapi_stable_builders() -> None:
     assert "stable" in all_builders[3].tags
 
 
+# The most recent builds in success.json and failure.json
+SUCCESS_COMPLETE_AT = 1728312495
+FAILURE_COMPLETE_AT = 1734198808
+DAY = buildbotapi.SECONDS_PER_DAY
+
+
 @pytest.mark.asyncio
 @pytest.mark.parametrize(
-    ["json_data", "expected"],
+    ["json_data", "now", "expected"],
     [
-        ("tests/buildbotapi/success.json", False),
-        ("tests/buildbotapi/failure.json", True),
-        ("tests/buildbotapi/no-builds.json", False),
+        # Recent builds: judged on their result
+        ("tests/buildbotapi/success.json", SUCCESS_COMPLETE_AT + DAY, False),
+        ("tests/buildbotapi/failure.json", FAILURE_COMPLETE_AT + DAY, True),
+        ("tests/buildbotapi/no-builds.json", FAILURE_COMPLETE_AT + DAY, False),
+        # Just inside the staleness cutoff: failure still counts
+        ("tests/buildbotapi/failure.json", FAILURE_COMPLETE_AT + 13 * DAY, True),
+        # Stale build (last run > 14 days ago): builder ignored
+        ("tests/buildbotapi/failure.json", FAILURE_COMPLETE_AT + 15 * DAY, False),
     ],
 )
-async def test_buildbotapi_is_builder_failing_currently_yes(
-    json_data: str, expected: bool
+async def test_buildbotapi_is_builder_failing_currently(
+    monkeypatch: pytest.MonkeyPatch, json_data: str, now: int, expected: bool
 ) -> None:
     # Arrange
     mock_session = AsyncMock(aiohttp.ClientSession)
@@ -126,6 +137,7 @@ async def test_buildbotapi_is_builder_failing_currently_yes(
     mock_session.get.return_value.__aenter__.return_value.text.return_value = load(
         json_data
     )
+    monkeypatch.setattr("buildbotapi.time.time", lambda: now)
     api = buildbotapi.BuildBotAPI(mock_session)
     builder = buildbotapi.Builder(builderid=3)