diff --git a/tests/resources/xtks.csv b/tests/resources/xtks.csv
index 4fa97a40..ff3c3fb8 100644
--- a/tests/resources/xtks.csv
+++ b/tests/resources/xtks.csv
@@ -5138,3 +5138,258 @@
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+2021-12-14,2021-12-14 00:01:00,2021-12-14 06:00:00
+2021-12-15,2021-12-15 00:01:00,2021-12-15 06:00:00
+2021-12-16,2021-12-16 00:01:00,2021-12-16 06:00:00
+2021-12-17,2021-12-17 00:01:00,2021-12-17 06:00:00
+2021-12-20,2021-12-20 00:01:00,2021-12-20 06:00:00
+2021-12-21,2021-12-21 00:01:00,2021-12-21 06:00:00
+2021-12-22,2021-12-22 00:01:00,2021-12-22 06:00:00
+2021-12-23,2021-12-23 00:01:00,2021-12-23 06:00:00
+2021-12-24,2021-12-24 00:01:00,2021-12-24 06:00:00
+2021-12-27,2021-12-27 00:01:00,2021-12-27 06:00:00
+2021-12-28,2021-12-28 00:01:00,2021-12-28 06:00:00
+2021-12-29,2021-12-29 00:01:00,2021-12-29 06:00:00
+2021-12-30,2021-12-30 00:01:00,2021-12-30 06:00:00
diff --git a/tests/test_xtks_calendar.py b/tests/test_xtks_calendar.py
index 20d96d1c..749d022d 100644
--- a/tests/test_xtks_calendar.py
+++ b/tests/test_xtks_calendar.py
@@ -230,3 +230,30 @@ def test_2020(self):
 
         for session_label in expected_holidays_2020:
             self.assertNotIn(session_label, self.calendar.all_sessions)
+
+    def test_2021(self):
+        expected_holidays_2021 = [
+            pd.Timestamp("2021-01-01", tz="UTC"),  # New Year's Day
+            pd.Timestamp("2021-01-02", tz="UTC"),  # Market Holiday
+            pd.Timestamp("2021-01-03", tz="UTC"),  # Market Holiday
+            pd.Timestamp("2021-01-11", tz="UTC"),  # Coming of Age Day
+            pd.Timestamp("2021-02-11", tz="UTC"),  # National Foundation Day
+            pd.Timestamp("2021-02-23", tz="UTC"),  # Emperor's Birthday
+            pd.Timestamp("2021-03-20", tz="UTC"),  # Vernal Equinox
+            pd.Timestamp("2021-04-29", tz="UTC"),  # Showa Day
+            pd.Timestamp("2021-05-03", tz="UTC"),  # Constitution Memorial Day
+            pd.Timestamp("2021-05-04", tz="UTC"),  # Greenery Day
+            pd.Timestamp("2021-05-05", tz="UTC"),  # Children's Day
+            pd.Timestamp("2021-07-22", tz="UTC"),  # Marine Day
+            pd.Timestamp("2021-07-23", tz="UTC"),  # Sports Day
+            pd.Timestamp("2021-08-08", tz="UTC"),  # Mountain Day
+            pd.Timestamp("2021-08-09", tz="UTC"),  # Mountain Day observed
+            pd.Timestamp("2021-09-20", tz="UTC"),  # Respect for the Aged Day
+            pd.Timestamp("2021-09-23", tz="UTC"),  # Autumnal Equinox
+            pd.Timestamp("2021-11-03", tz="UTC"),  # Culture Day
+            pd.Timestamp("2021-11-23", tz="UTC"),  # Labor Thanksgiving Day
+            pd.Timestamp("2021-12-31", tz="UTC"),  # Market Holiday
+        ]
+
+        for session_label in expected_holidays_2021:
+            self.assertNotIn(session_label, self.calendar.all_sessions)
diff --git a/trading_calendars/exchange_calendar_xtks.py b/trading_calendars/exchange_calendar_xtks.py
index f6601ba9..9672301f 100644
--- a/trading_calendars/exchange_calendar_xtks.py
+++ b/trading_calendars/exchange_calendar_xtks.py
@@ -27,17 +27,20 @@
     MarineDayThrough2002,
     MarineDay2003OnwardsThrough2019,
     MarineDay2020,
-    MarineDay2021Onwards,
+    MarineDay2021,
+    MarineDay2022Onwards,
     MountainDayThrough2019,
     MountainDay2020,
-    MountainDay2021Onwards,
+    MountainDay2021,
+    MountainDay2022Onwards,
     AutumnalEquinoxes,
     CitizensHolidaySilverWeek,
     RespectForTheAgedDayThrough2002,
     RespectForTheAgedDay2003Onwards,
     HealthAndSportsDayThrough2019,
     HealthAndSportsDay2020,
-    HealthAndSportsDay2021Onwards,
+    HealthAndSportsDay2021,
+    HealthAndSportsDay2022Onwards,
     CultureDay,
     LaborThanksgivingDay,
     EmperorAkihitoBirthday,
@@ -115,15 +118,18 @@ def regular_holidays(self):
             MarineDayThrough2002,
             MarineDay2003OnwardsThrough2019,
             MarineDay2020,
-            MarineDay2021Onwards,
+            MarineDay2021,
+            MarineDay2022Onwards,
             MountainDayThrough2019,
             MountainDay2020,
-            MountainDay2021Onwards,
+            MountainDay2021,
+            MountainDay2022Onwards,
             RespectForTheAgedDayThrough2002,
             RespectForTheAgedDay2003Onwards,
             HealthAndSportsDayThrough2019,
             HealthAndSportsDay2020,
-            HealthAndSportsDay2021Onwards,
+            HealthAndSportsDay2021,
+            HealthAndSportsDay2022Onwards,
             CultureDay,
             LaborThanksgivingDay,
             EmperorAkihitoBirthday,
diff --git a/trading_calendars/xtks_holidays.py b/trading_calendars/xtks_holidays.py
index 75c78ce8..2e9297d5 100644
--- a/trading_calendars/xtks_holidays.py
+++ b/trading_calendars/xtks_holidays.py
@@ -87,7 +87,8 @@ def sunday_to_wednesday(dt):
     Timestamp('2017-03-20'),
     Timestamp('2018-03-21'),
     Timestamp('2019-03-21'),
-    Timestamp('2020-03-20')
+    Timestamp('2020-03-20'),
+    Timestamp('2021-03-20'),
 ]
 
 # The Golden Week holidays (late April - early May) are listed in reverse
@@ -186,12 +187,19 @@ def sunday_to_wednesday(dt):
     year=2020,
 )
 
-MarineDay2021Onwards = Holiday(
-    "Marine Day (2021 onwards)",
+MarineDay2021 = Holiday(
+    "Marine Day (2021)",
+    month=7,
+    day=22,
+    year=2021,
+)
+
+MarineDay2022Onwards = Holiday(
+    "Marine Day (2022 onwards)",
     month=7,
     day=1,
     offset=DateOffset(weekday=MO(3)),
-    start_date='2021-01-01',
+    start_date='2022-01-01',
 )
 
 MountainDayThrough2019 = Holiday(
@@ -211,11 +219,18 @@ def sunday_to_wednesday(dt):
     year=2020,
 )
 
-MountainDay2021Onwards = Holiday(
-    "Mountain Day (2021 onwards)",
+MountainDay2021 = Holiday(
+    "Mountain Day (2021)",
+    month=8,
+    day=9,
+    year=2021,
+)
+
+MountainDay2022Onwards = Holiday(
+    "Mountain Day (2022 onwards)",
     month=8,
     day=11,
-    start_date="2021-01-01",
+    start_date="2022-01-01",
     observance=sunday_to_monday,
 )
 
@@ -242,6 +257,7 @@ def sunday_to_wednesday(dt):
     Timestamp('2018-09-24'),
     Timestamp('2019-09-23'),
     Timestamp('2020-09-22'),
+    Timestamp('2021-09-23'),
 ]
 
 # If the Autumnal Equinox falls on a Wednesday, the Tuesday before
@@ -285,12 +301,19 @@ def sunday_to_wednesday(dt):
     year=2020,
 )
 
-HealthAndSportsDay2021Onwards = Holiday(
-    "Health and Sports Day (2021 onwards)",
+HealthAndSportsDay2021 = Holiday(
+    "Health and Sports Day (2021)",
+    month=7,
+    day=23,
+    year=2021,
+)
+
+HealthAndSportsDay2022Onwards = Holiday(
+    "Health and Sports Day (2022 onwards)",
     month=10,
     day=1,
     offset=DateOffset(weekday=MO(2)),
-    start_date="2021-01-01",
+    start_date="2022-01-01",
 )
 
 CultureDay = Holiday(