diff --git a/plexpy/__init__.py b/plexpy/__init__.py
index 0366fcde..21b5ef6d 100644
--- a/plexpy/__init__.py
+++ b/plexpy/__init__.py
@@ -1504,6 +1504,18 @@ def dbcheck():
     except sqlite3.OperationalError:
         logger.warn("Unable to capitalize Windows platform values in session_history table.")
 
+    # Upgrade session_history table from earlier versions
+    try:
+        result = c_db.execute("SELECT platform FROM session_history "
+                              "WHERE platform = 'macos'").fetchall()
+        if len(result) > 0:
+            logger.debug("Altering database. Capitalizing macOS platform values in session_history table.")
+            c_db.execute(
+                "UPDATE session_history SET platform = 'macOS' WHERE platform = 'macos' "
+            )
+    except sqlite3.OperationalError:
+        logger.warn("Unable to capitalize macOS platform values in session_history table.")
+
     # Upgrade session_history_metadata table from earlier versions
     try:
         c_db.execute("SELECT full_title FROM session_history_metadata")
diff --git a/plexpy/common.py b/plexpy/common.py
index fb35beb3..8d68e2ad 100644
--- a/plexpy/common.py
+++ b/plexpy/common.py
@@ -102,7 +102,8 @@ PLATFORM_NAME_OVERRIDES = {
     'Mystery 5': 'Xbox 360',
     'WebMAF': 'Playstation 4',
     'windows': 'Windows',
-    'osx': 'macOS'
+    'osx': 'macOS',
+    'macos': 'macOS',
 }
 
 PMS_PLATFORM_NAME_OVERRIDES = {