diff --git a/src/slack-bot/app.py b/src/slack-bot/app.py
index a446891..6a30d7b 100644
--- a/src/slack-bot/app.py
+++ b/src/slack-bot/app.py
@@ -62,6 +62,7 @@ _DATED_FORMATS = (
     "%Y-%m-%d",
     "%m/%d/%Y",
     "%m/%d/%y",
+    "%m-%d-%Y",
     "%m-%d-%y",
     "%b %d %Y",
     "%B %d %Y",
diff --git a/tests/slack_bot/test_parse_date.py b/tests/slack_bot/test_parse_date.py
index 0b2d36c..3b9c778 100644
--- a/tests/slack_bot/test_parse_date.py
+++ b/tests/slack_bot/test_parse_date.py
@@ -69,6 +69,19 @@ def test_two_digit_year_dash(slackbot_app):
     assert slackbot_app.parse_date("7-3-26").strftime("%Y-%m-%d") == "2026-07-03"
 
 
+@freeze_time(FROZEN)
+def test_four_digit_year_dash(slackbot_app):
+    assert slackbot_app.parse_date("7-3-2026").strftime("%Y-%m-%d") == "2026-07-03"
+
+
+@freeze_time(FROZEN)
+def test_two_digit_year_century_boundary(slackbot_app):
+    # Python's %y maps 00–68 → 2000s and 69–99 → 1900s. Pin it so nobody
+    # "fixes" the ambiguity by accident later.
+    assert slackbot_app.parse_date("12/31/99").year == 1999
+    assert slackbot_app.parse_date("1/1/68").year == 2068
+
+
 @freeze_time(FROZEN)
 def test_two_digit_year_past_not_rolled(slackbot_app):
     # Explicit two-digit year in the past stays put — no roll-forward.