diff --git a/packages/eui/src/components/date_picker/react-datepicker/src/calendar.js b/packages/eui/src/components/date_picker/react-datepicker/src/calendar.js
index 64b9f2c8ff3..74038d51d66 100644
--- a/packages/eui/src/components/date_picker/react-datepicker/src/calendar.js
+++ b/packages/eui/src/components/date_picker/react-datepicker/src/calendar.js
@@ -358,15 +358,8 @@ export default class Calendar extends React.Component {
       [0, 1, 2, 3, 4, 5, 6].map(offset => {
         const day = addDays(cloneDate(startOfWeek), offset);
         const localeData = getLocaleData(day);
-        const localeStartDayOfWeek = localeData._week.dow;
-
-        const weekStartDayIndex = localeStartDayOfWeek + offset;
-        // determine the current day index based on the week starting day (Sunday vs Monday)
-        const currentDayIndex =
-          weekStartDayIndex < 7 ? weekStartDayIndex : 7 - weekStartDayIndex;
-
         const weekDayName = this.formatWeekday(localeData, day);
-        const weekDayNameLong = localeData._weekdays[currentDayIndex]
+        const weekDayNameLong = localeData.weekdays(day);
 
         return (
           <div key={offset} className="react-datepicker__day-name">