diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6103fb1..e00aaa3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -25,6 +25,7 @@ and this project adheres to
 
 ### Fixed
 
+- Fix leaked file handles in tests using context managers ([b66a6f5], [#25])
 - Fix typo in test name: `test_l9events_form_ip4scout` ->
   `test_l9events_from_ip4scout` ([0d8736e], [#27])
 
@@ -150,6 +151,7 @@ and this project adheres to
 
 <!-- Commit links -->
 
+[b66a6f5]: https://github.com/LeakIX/l9format-python/commit/b66a6f5
 [3547e22]: https://github.com/LeakIX/l9format-python/commit/3547e22
 [1ca6e4d]: https://github.com/LeakIX/l9format-python/commit/1ca6e4d
 [0d8736e]: https://github.com/LeakIX/l9format-python/commit/0d8736e
@@ -218,4 +220,5 @@ and this project adheres to
 [#22]: https://github.com/LeakIX/l9format-python/issues/22
 [#27]: https://github.com/LeakIX/l9format-python/issues/27
 [#33]: https://github.com/LeakIX/l9format-python/issues/33
+[#25]: https://github.com/LeakIX/l9format-python/issues/25
 [#35]: https://github.com/LeakIX/l9format-python/issues/35
diff --git a/tests/test_l9format.py b/tests/test_l9format.py
index 01edfd6..51e58ed 100644
--- a/tests/test_l9format.py
+++ b/tests/test_l9format.py
@@ -1,10 +1,9 @@
 import json
-import os
 from pathlib import Path
 
 from l9format import L9Event
 
-TESTS_DIR = Path(os.path.dirname(__file__))
+TESTS_DIR = Path(__file__).parent
 
 IP4SCOUT_FILES = [
     f
@@ -15,13 +14,15 @@
 
 def test_l9event_json_from_reference_repository():
     path = TESTS_DIR / "l9event.json"
-    c = json.load(open(str(path), "r"))
+    with open(path) as f:
+        c = json.load(f)
     L9Event.from_dict(c)
 
 
 def test_l9events_from_ip4scout():
     for path in IP4SCOUT_FILES:
-        c = json.load(open(str(path), "r"))
+        with open(path) as f:
+            c = json.load(f)
         L9Event.from_dict(c)
 
 
@@ -33,7 +34,8 @@ def test_iso8601_nanosecond_parsing():
     correctly in Python 3.11+.
     """
     path = TESTS_DIR / "l9event.json"
-    c = json.load(open(str(path), "r"))
+    with open(path) as f:
+        c = json.load(f)
     # Use a timestamp with nanosecond precision (9 decimal places)
     c["time"] = "2023-10-05T23:30:36.823867784Z"
     event = L9Event.from_dict(c)