diff --git a/code/modules/holiday/dynamic.dm b/code/modules/holiday/dynamic.dm
index fb50ea72ca..f75dd37542 100644
--- a/code/modules/holiday/dynamic.dm
+++ b/code/modules/holiday/dynamic.dm
@@ -3,7 +3,7 @@
 
 /datum/holiday/dynamic/shouldCelebrate(dd, mm, yy, ww, ddd)
 	var/list/days = CONFIG_GET(keyed_list/dynamic_mode_days)
-	return ddd in days
+	return lowertext(ddd) in days
 
 /datum/holiday/dynamic/celebrate()
 	GLOB.dynamic_forced_threat_level = rand(90, 100)