diff --git a/docusaurus/docs/date-picker/input-date-picker.md b/docusaurus/docs/date-picker/input-date-picker.md
index 74a1eadd..58d8cf67 100644
--- a/docusaurus/docs/date-picker/input-date-picker.md
+++ b/docusaurus/docs/date-picker/input-date-picker.md
@@ -119,6 +119,10 @@ The start year when the component is rendered. Defaults to `1800`.
 `Type: number | undefined`  
 The end year when the component is rendered. Defaults to `2200`.
 
+**startWeekOnMonday**  
+`Type: boolean | undefined`  
+Flag indicating if calendar grid sould show monday as the first column. Defaults to `false`.
+
 **inputEnabled**  
 `Type: boolean | undefined`  
 Flag indicating if the component should be enabled or not. Behavior similarly to `disabled`. Defaults to `true`.
diff --git a/docusaurus/docs/date-picker/multiple-dates-picker.md b/docusaurus/docs/date-picker/multiple-dates-picker.md
index de00f3b4..571ebe4b 100644
--- a/docusaurus/docs/date-picker/multiple-dates-picker.md
+++ b/docusaurus/docs/date-picker/multiple-dates-picker.md
@@ -131,6 +131,10 @@ The start year when the component is rendered. Defaults to `1800`.
 `Type: number | undefined`  
 The end year when the component is rendered. Defaults to `2200`.
 
+**startWeekOnMonday**  
+`Type: boolean | undefined`  
+Flag indicating if calendar grid sould show monday as the first column. Defaults to `false`.
+
 **closeIcon**  
 `Type: string | undefined`  
 The icon used to close the component. Defaults to `close`. You can pass the name of an icon from [MaterialCommunityIcons](https://materialdesignicons.com/).
diff --git a/docusaurus/docs/date-picker/range-date-picker.md b/docusaurus/docs/date-picker/range-date-picker.md
index bb9ddd63..76e09a78 100644
--- a/docusaurus/docs/date-picker/range-date-picker.md
+++ b/docusaurus/docs/date-picker/range-date-picker.md
@@ -134,6 +134,10 @@ The start year when the component is rendered. Defaults to `1800`.
 `Type: number | undefined`  
 The end year when the component is rendered. Defaults to `2200`.
 
+**startWeekOnMonday**  
+`Type: boolean | undefined`  
+Flag indicating if calendar grid sould show monday as the first column. Defaults to `false`.
+
 **closeIcon**  
 `Type: string | undefined`  
 The icon used to close the component. Defaults to `close`. You can pass the name of an icon from [MaterialCommunityIcons](https://materialdesignicons.com/).
diff --git a/docusaurus/docs/date-picker/single-date-picker.md b/docusaurus/docs/date-picker/single-date-picker.md
index 8d3d573c..b68bc3d9 100644
--- a/docusaurus/docs/date-picker/single-date-picker.md
+++ b/docusaurus/docs/date-picker/single-date-picker.md
@@ -121,6 +121,10 @@ The start year when the component is rendered. Defaults to `1800`.
 `Type: number | undefined`  
 The end year when the component is rendered. Defaults to `2200`.
 
+**startWeekOnMonday**  
+`Type: boolean | undefined`  
+Flag indicating if calendar grid sould show monday as the first column. Defaults to `false`.
+
 **closeIcon**  
 `Type: string | undefined`  
 The icon used to close the component. Defaults to `close`. You can pass the name of an icon from [MaterialCommunityIcons](https://materialdesignicons.com/).
diff --git a/example/src/ReadMeExampleMultiple.tsx b/example/src/ReadMeExampleMultiple.tsx
index b42ae45f..5fd6a627 100644
--- a/example/src/ReadMeExampleMultiple.tsx
+++ b/example/src/ReadMeExampleMultiple.tsx
@@ -44,6 +44,7 @@ export default function ReadMeExampleMultiple() {
         // animationType="slide" // optional, default is slide on ios/android and none on web
         // startYear={2000} // optional, default is 1800
         // endYear={2100} // optional, default is 2200
+        // startWeekOnMonday={true} // optional, default is false
       />
     </>
   )
diff --git a/example/src/ReadMeExampleRange.tsx b/example/src/ReadMeExampleRange.tsx
index 12d24d2e..e00802df 100644
--- a/example/src/ReadMeExampleRange.tsx
+++ b/example/src/ReadMeExampleRange.tsx
@@ -52,6 +52,7 @@ export default function ReadMeExampleRange() {
         // animationType="slide" // optional, default is slide on ios/android and none on web
         // startYear={2000} // optional, default is 1800
         // endYear={2100} // optional, default is 2200
+        // startWeekOnMonday={true} // optional, default is false
       />
     </>
   )
diff --git a/example/src/ReadMeExampleSingle.tsx b/example/src/ReadMeExampleSingle.tsx
index 6e4c2f5f..cd18b4cb 100644
--- a/example/src/ReadMeExampleSingle.tsx
+++ b/example/src/ReadMeExampleSingle.tsx
@@ -43,6 +43,7 @@ export default function ReadMeExampleSingle() {
         // animationType="slide" // optional, default is 'slide' on ios/android and 'none' on web
         // startYear={2000} // optional, default is 1800
         // endYear={2100} // optional, default is 2200
+        // startWeekOnMonday={true} // optional, default is false
         //
       />
     </>
diff --git a/src/Date/Calendar.tsx b/src/Date/Calendar.tsx
index 76dbc538..780e7036 100644
--- a/src/Date/Calendar.tsx
+++ b/src/Date/Calendar.tsx
@@ -33,6 +33,7 @@ export type BaseCalendarProps = {
   validRange?: ValidRangeType
   startYear?: number
   endYear?: number
+  startWeekOnMonday?: boolean
 
   // here they are optional but in final implementation they are required
   date?: CalendarDate
@@ -95,6 +96,7 @@ function Calendar(
     dates,
     validRange,
     dateMode,
+    startWeekOnMonday,
   } = props
 
   const theme = useTheme()
@@ -177,6 +179,7 @@ function Calendar(
         initialIndex={getInitialIndex(firstDate)}
         selectedYear={selectedYear}
         scrollMode={scrollMode}
+        startWeekOnMonday={startWeekOnMonday || false}
         renderItem={({ index }) => (
           <Month
             locale={locale}
@@ -196,6 +199,7 @@ function Calendar(
             selectColor={selectColor}
             roundness={theme.roundness}
             disableWeekDays={disableWeekDays}
+            startWeekOnMonday={startWeekOnMonday || false}
           />
         )}
         renderHeader={({ onPrev, onNext }) => (
@@ -205,6 +209,7 @@ function Calendar(
             onNext={onNext}
             scrollMode={scrollMode}
             disableWeekDays={disableWeekDays}
+            startWeekOnMonday={startWeekOnMonday || false}
           />
         )}
       />
diff --git a/src/Date/CalendarHeader.tsx b/src/Date/CalendarHeader.tsx
index d95206b2..1b845200 100644
--- a/src/Date/CalendarHeader.tsx
+++ b/src/Date/CalendarHeader.tsx
@@ -27,12 +27,14 @@ function CalendarHeader({
   onNext,
   disableWeekDays,
   locale,
+  startWeekOnMonday,
 }: {
   locale: undefined | string
   scrollMode: 'horizontal' | 'vertical'
   onPrev: () => any
   onNext: () => any
   disableWeekDays?: DisableWeekDaysType
+  startWeekOnMonday: boolean
 }) {
   const theme = useTheme()
   const isHorizontal = scrollMode === 'horizontal'
@@ -67,7 +69,11 @@ function CalendarHeader({
           </View>
         </View>
       ) : null}
-      <DayNames disableWeekDays={disableWeekDays} locale={locale} />
+      <DayNames
+        disableWeekDays={disableWeekDays}
+        locale={locale}
+        startWeekOnMonday={startWeekOnMonday}
+      />
     </View>
   )
 }
diff --git a/src/Date/DatePickerInput.shared.tsx b/src/Date/DatePickerInput.shared.tsx
index 44b71df0..bb0f896f 100644
--- a/src/Date/DatePickerInput.shared.tsx
+++ b/src/Date/DatePickerInput.shared.tsx
@@ -27,6 +27,7 @@ export type DatePickerInputProps = {
   disableStatusBarPadding?: boolean
   animationType?: 'slide' | 'fade' | 'none'
   presentationStyle?: 'pageSheet' | 'overFullScreen'
+  startWeekOnMonday?: boolean
 } & Omit<
   React.ComponentProps<typeof TextInput>,
   'value' | 'onChange' | 'onChangeText' | 'inputMode'
diff --git a/src/Date/DatePickerInput.tsx b/src/Date/DatePickerInput.tsx
index fc5608c7..2decd08f 100644
--- a/src/Date/DatePickerInput.tsx
+++ b/src/Date/DatePickerInput.tsx
@@ -60,6 +60,7 @@ function DatePickerInput(
         endYear,
         inputEnabled,
         disableStatusBarPadding,
+        startWeekOnMonday,
       }) =>
         withModal ? (
           <DatePickerModal
@@ -81,6 +82,7 @@ function DatePickerInput(
             animationType={animationType}
             presentationStyle={presentationStyle}
             label={rest.label as any}
+            startWeekOnMonday={startWeekOnMonday}
           />
         ) : null
       }
diff --git a/src/Date/DatePickerInputWithoutModal.tsx b/src/Date/DatePickerInputWithoutModal.tsx
index d86d6ef8..47d0be2c 100644
--- a/src/Date/DatePickerInputWithoutModal.tsx
+++ b/src/Date/DatePickerInputWithoutModal.tsx
@@ -29,6 +29,7 @@ function DatePickerInputWithoutModal(
     onChangeText,
     inputEnabled,
     disableStatusBarPadding,
+    startWeekOnMonday,
     ...rest
   }: DatePickerInputProps & {
     modal?: (params: {
@@ -43,6 +44,7 @@ function DatePickerInputWithoutModal(
       endYear: DatePickerInputProps['endYear']
       inputEnabled: DatePickerInputProps['inputEnabled']
       disableStatusBarPadding: DatePickerInputProps['disableStatusBarPadding']
+      startWeekOnMonday?: DatePickerInputProps['startWeekOnMonday']
     }) => any
     inputButton?: React.ReactNode
   },
@@ -118,6 +120,7 @@ function DatePickerInputWithoutModal(
         endYear,
         inputEnabled,
         disableStatusBarPadding,
+        startWeekOnMonday,
       })}
     </>
   )
diff --git a/src/Date/DatePickerModalContent.tsx b/src/Date/DatePickerModalContent.tsx
index 08b2877f..98f91fef 100644
--- a/src/Date/DatePickerModalContent.tsx
+++ b/src/Date/DatePickerModalContent.tsx
@@ -93,6 +93,7 @@ export function DatePickerModalContent(
     startYear,
     endYear,
     statusBarOnTopOfBackdrop,
+    startWeekOnMonday,
   } = props
   const anyProps = props as any
 
@@ -199,6 +200,7 @@ export function DatePickerModalContent(
             dateMode={dateMode}
             startYear={startYear}
             endYear={endYear}
+            startWeekOnMonday={startWeekOnMonday}
           />
         }
         calendarEdit={
diff --git a/src/Date/DayNames.tsx b/src/Date/DayNames.tsx
index 898969c0..6584cd9c 100644
--- a/src/Date/DayNames.tsx
+++ b/src/Date/DayNames.tsx
@@ -6,31 +6,35 @@ import { DisableWeekDaysType, showWeekDay } from './dateUtils'
 
 export const dayNamesHeight = 44
 
-// TODO: wait for a better Intl api ;-)
-const weekdays = [
-  new Date(2020, 7, 2),
-  new Date(2020, 7, 3),
-  new Date(2020, 7, 4),
-  new Date(2020, 7, 5),
-  new Date(2020, 7, 6),
-  new Date(2020, 7, 7),
-  new Date(2020, 7, 8),
-]
-
 function DayNames({
   disableWeekDays,
   locale,
+  startWeekOnMonday,
 }: {
   locale: undefined | string
   disableWeekDays?: DisableWeekDaysType
+  startWeekOnMonday: boolean
 }) {
   const theme = useTheme()
   const shortDayNames = React.useMemo<string[]>(() => {
+    // TODO: wait for a better Intl api ;-)
+    const weekdays = [
+      new Date(2020, 7, 2),
+      new Date(2020, 7, 3),
+      new Date(2020, 7, 4),
+      new Date(2020, 7, 5),
+      new Date(2020, 7, 6),
+      new Date(2020, 7, 7),
+      new Date(2020, 7, 8),
+    ]
+    if (startWeekOnMonday) {
+      weekdays.push(weekdays.shift() as Date)
+    }
     const formatter = new Intl.DateTimeFormat(locale, {
       weekday: 'narrow',
     })
     return weekdays.map((date) => formatter.format(date))
-  }, [locale])
+  }, [locale, startWeekOnMonday])
 
   return (
     <View
diff --git a/src/Date/Month.tsx b/src/Date/Month.tsx
index 9a8e3fb4..6bab2ee2 100644
--- a/src/Date/Month.tsx
+++ b/src/Date/Month.tsx
@@ -49,6 +49,7 @@ interface BaseMonthProps {
   selectColor: string
   roundness: number
   validRange?: ValidRangeType
+  startWeekOnMonday: boolean
 
   // some of these should be required in final implementation
   startDate?: CalendarDate
@@ -91,6 +92,7 @@ function Month(props: MonthSingleProps | MonthRangeProps | MonthMultiProps) {
     disableWeekDays,
     locale,
     validRange,
+    startWeekOnMonday,
   } = props
   const theme = useTheme()
   const textColorOnPrimary = useTextColorOnPrimary()
@@ -111,10 +113,10 @@ function Month(props: MonthSingleProps | MonthRangeProps | MonthMultiProps) {
     const today = new Date()
 
     const daysInMonth = getDaysInMonth({ year, month })
-    const dayOfWeek = getFirstDayOfMonth({ year, month })
+    const dayOfWeek = getFirstDayOfMonth({ year, month, startWeekOnMonday })
     const emptyDays = dayOfWeek
 
-    return monthGrid(index).map(({ days, weekGrid }) => {
+    return monthGrid(index, startWeekOnMonday).map(({ days, weekGrid }) => {
       return {
         weekIndex: weekGrid,
         generatedDays: days.map((_, dayIndex) => {
@@ -248,6 +250,7 @@ function Month(props: MonthSingleProps | MonthRangeProps | MonthMultiProps) {
     endDate,
     dates,
     date,
+    startWeekOnMonday,
   ])
 
   let textFont = theme?.isV3
@@ -263,7 +266,12 @@ function Month(props: MonthSingleProps | MonthRangeProps | MonthMultiProps) {
   const iconSource = theme.isV3 ? iconSourceV3 : iconSourceV2
 
   return (
-    <View style={[styles.month, { height: getMonthHeight(scrollMode, index) }]}>
+    <View
+      style={[
+        styles.month,
+        { height: getMonthHeight(scrollMode, index, startWeekOnMonday) },
+      ]}
+    >
       <View
         style={[
           styles.monthHeader,
@@ -388,8 +396,8 @@ const styles = StyleSheet.create({
   opacity1: { opacity: 1 },
 })
 
-const monthGrid = (index: number) => {
-  return Array(getGridCount(index))
+const monthGrid = (index: number, startWeekOnMonday: boolean) => {
+  return Array(getGridCount(index, startWeekOnMonday))
     .fill(null)
     .map((_, weekGrid) => {
       const days = Array(7).fill(null)
@@ -405,7 +413,7 @@ function getIndexCount(index: number): number {
   return -(startAtIndex - index)
 }
 
-function weeksOffset(index: number): number {
+function weeksOffset(index: number, startWeekOnMonday: boolean): number {
   if (index === startAtIndex) {
     return 0
   }
@@ -413,12 +421,12 @@ function weeksOffset(index: number): number {
   if (index > startAtIndex) {
     for (let i = 0; i < index - startAtIndex; i++) {
       const cIndex = startAtIndex + i
-      off += gridCounts[cIndex] || getGridCount(cIndex)
+      off += gridCounts[cIndex] || getGridCount(cIndex, startWeekOnMonday)
     }
   } else {
     for (let i = 0; i < startAtIndex - index; i++) {
       const cIndex = startAtIndex - i - 1
-      off -= gridCounts[cIndex] || getGridCount(cIndex)
+      off -= gridCounts[cIndex] || getGridCount(cIndex, startWeekOnMonday)
     }
   }
   return off
@@ -431,10 +439,13 @@ export function getIndexFromHorizontalOffset(
   return startAtIndex + Math.floor(offset / width)
 }
 
-export function getIndexFromVerticalOffset(offset: number): number {
+export function getIndexFromVerticalOffset(
+  offset: number,
+  startWeekOnMonday: boolean
+): number {
   let estimatedIndex = startAtIndex + Math.ceil(offset / estimatedMonthHeight)
 
-  const realOffset = getVerticalMonthsOffset(estimatedIndex)
+  const realOffset = getVerticalMonthsOffset(estimatedIndex, startWeekOnMonday)
   const difference = (realOffset - beginOffset - offset) / estimatedMonthHeight
   if (difference >= 1 || difference <= -1) {
     estimatedIndex -= Math.floor(difference)
@@ -449,9 +460,12 @@ export function getHorizontalMonthOffset(index: number, width: number) {
   return width * index
 }
 
-export function getVerticalMonthsOffset(index: number) {
+export function getVerticalMonthsOffset(
+  index: number,
+  startWeekOnMonday: boolean
+) {
   const count = getIndexCount(index)
-  const ob = weeksOffset(index)
+  const ob = weeksOffset(index, startWeekOnMonday)
   const monthsHeight = weekSize * ob
   const c = monthsHeight + count * (dayNamesHeight + montHeaderHeight)
 
@@ -460,10 +474,11 @@ export function getVerticalMonthsOffset(index: number) {
 
 export function getMonthHeight(
   scrollMode: 'horizontal' | 'vertical',
-  index: number
+  index: number,
+  startWeekOnMonday: boolean
 ): number {
   const calendarHeight = getCalendarHeaderHeight(scrollMode)
-  const gc = getGridCount(index)
+  const gc = getGridCount(index, startWeekOnMonday)
 
   const currentMonthHeight = weekSize * gc
   const extraHeight =
diff --git a/src/Date/Swiper.native.tsx b/src/Date/Swiper.native.tsx
index f80d2ccf..28278536 100644
--- a/src/Date/Swiper.native.tsx
+++ b/src/Date/Swiper.native.tsx
@@ -56,6 +56,7 @@ function SwiperInner({
   initialIndex,
   width,
   height,
+  startWeekOnMonday,
 }: SwiperProps & { width: number; height: number }) {
   const idx = React.useRef<number>(initialIndex)
   const isHorizontal = scrollMode === 'horizontal'
@@ -75,7 +76,7 @@ function SwiperInner({
       }
       const offset = isHorizontal
         ? getHorizontalMonthOffset(index, width)
-        : getVerticalMonthsOffset(index) - montHeaderHeight
+        : getVerticalMonthsOffset(index, startWeekOnMonday) - montHeaderHeight
 
       if (isHorizontal) {
         parentRef.current.scrollTo({
@@ -91,7 +92,7 @@ function SwiperInner({
         })
       }
     },
-    [parentRef, isHorizontal, width, height]
+    [parentRef, isHorizontal, width, height, startWeekOnMonday]
   )
 
   const onPrev = React.useCallback(() => {
@@ -112,7 +113,10 @@ function SwiperInner({
       const viewSize = e.nativeEvent.layoutMeasurement
       const newIndex = isHorizontal
         ? Math.floor(contentOffset.x / viewSize.width)
-        : getIndexFromVerticalOffset(contentOffset.y - beginOffset)
+        : getIndexFromVerticalOffset(
+            contentOffset.y - beginOffset,
+            startWeekOnMonday
+          )
 
       if (newIndex === 0) {
         return
@@ -123,7 +127,7 @@ function SwiperInner({
         setVisibleIndexes(getVisibleArray(newIndex, { isHorizontal, height }))
       }
     },
-    [idx, height, isHorizontal]
+    [idx, height, isHorizontal, startWeekOnMonday]
   )
 
   const renderProps = {
@@ -179,7 +183,10 @@ function SwiperInner({
                   style={{
                     top: isHorizontal
                       ? 0
-                      : getVerticalMonthsOffset(visibleIndexes[vi]),
+                      : getVerticalMonthsOffset(
+                          visibleIndexes[vi],
+                          startWeekOnMonday
+                        ),
                     left: isHorizontal
                       ? getHorizontalMonthOffset(visibleIndexes[vi], width)
                       : 0,
@@ -189,7 +196,11 @@ function SwiperInner({
                     width: isHorizontal ? width : undefined,
                     height: isHorizontal
                       ? undefined
-                      : getMonthHeight(scrollMode, visibleIndexes[vi]),
+                      : getMonthHeight(
+                          scrollMode,
+                          visibleIndexes[vi],
+                          startWeekOnMonday
+                        ),
                   }}
                 >
                   {renderItem({
diff --git a/src/Date/Swiper.tsx b/src/Date/Swiper.tsx
index 33f3ccd2..2cfe90de 100644
--- a/src/Date/Swiper.tsx
+++ b/src/Date/Swiper.tsx
@@ -20,6 +20,7 @@ function Swiper({
   renderFooter,
   selectedYear,
   initialIndex,
+  startWeekOnMonday,
 }: SwiperProps) {
   const isHorizontal = scrollMode === 'horizontal'
   const [index, setIndex] = React.useState(initialIndex)
@@ -66,6 +67,7 @@ function Swiper({
               initialIndex={initialIndex}
               estimatedHeight={estimatedMonthHeight}
               renderItem={renderItem}
+              startWeekOnMonday={startWeekOnMonday}
             />
           )}
         </AutoSizer>
@@ -83,12 +85,14 @@ function VerticalScroller({
   initialIndex,
   estimatedHeight,
   renderItem,
+  startWeekOnMonday,
 }: {
   renderItem: (renderProps: RenderProps) => any
   width: number
   height: number
   initialIndex: number
   estimatedHeight: number
+  startWeekOnMonday: boolean
 }) {
   const idx = React.useRef<number>(initialIndex)
   const [visibleIndexes, setVisibleIndexes] = React.useState<number[]>(
@@ -101,7 +105,8 @@ function VerticalScroller({
     if (!element) {
       return
     }
-    const top = getVerticalMonthsOffset(idx.current) - montHeaderHeight
+    const top =
+      getVerticalMonthsOffset(idx.current, startWeekOnMonday) - montHeaderHeight
 
     element.scrollTo({
       top,
@@ -118,14 +123,14 @@ function VerticalScroller({
       }
 
       const offset = top - beginOffset
-      const index = getIndexFromVerticalOffset(offset)
+      const index = getIndexFromVerticalOffset(offset, startWeekOnMonday)
 
       if (idx.current !== index) {
         idx.current = index
         setVisibleIndexesThrottled(visibleArray(index))
       }
     },
-    [setVisibleIndexesThrottled]
+    [setVisibleIndexesThrottled, startWeekOnMonday]
   )
 
   return (
@@ -153,12 +158,17 @@ function VerticalScroller({
             style={{
               willChange: 'transform',
               transform: `translateY(${getVerticalMonthsOffset(
-                visibleIndexes[vi]
+                visibleIndexes[vi],
+                startWeekOnMonday
               )}px)`,
               left: 0,
               right: 0,
               position: 'absolute',
-              height: getMonthHeight('vertical', visibleIndexes[vi]),
+              height: getMonthHeight(
+                'vertical',
+                visibleIndexes[vi],
+                startWeekOnMonday
+              ),
             }}
           >
             {renderItem({
diff --git a/src/Date/SwiperUtils.ts b/src/Date/SwiperUtils.ts
index 8a98be84..c6f6fd2a 100644
--- a/src/Date/SwiperUtils.ts
+++ b/src/Date/SwiperUtils.ts
@@ -21,6 +21,7 @@ export type SwiperProps = {
   renderHeader?: (renderProps: RenderProps) => any
   renderFooter?: (renderProps: RenderProps) => any
   selectedYear: number | undefined
+  startWeekOnMonday: boolean
 }
 
 export function useYearChange(
diff --git a/src/Date/dateUtils.tsx b/src/Date/dateUtils.tsx
index 26131a3a..c4a59ce1 100644
--- a/src/Date/dateUtils.tsx
+++ b/src/Date/dateUtils.tsx
@@ -58,11 +58,19 @@ export function getDaysInMonth({
 export function getFirstDayOfMonth({
   year,
   month,
+  startWeekOnMonday,
 }: {
   year: number
   month: number
+  startWeekOnMonday: boolean
 }): number {
-  return new Date(year, month, 1).getDay()
+  let dayOfWeek = new Date(year, month, 1).getDay()
+  if (startWeekOnMonday) {
+    // Map Sunday (0) to 6, Monday (1) to 0, etc.
+    dayOfWeek = (dayOfWeek + 6) % 7
+  }
+
+  return dayOfWeek
 }
 
 export function useRangeChecker(validRange: ValidRangeType | undefined) {
@@ -167,22 +175,22 @@ export const totalMonths = startAtIndex * 2
 export const beginOffset = estimatedMonthHeight * startAtIndex
 export const gridCounts = new Array<number | undefined>(totalMonths)
 
-export function getGridCount(index: number) {
+export function getGridCount(index: number, startWeekOnMonday: boolean) {
   const cHeight = gridCounts[index]
   if (cHeight) {
     return cHeight
   }
   const monthDate = addMonths(new Date(), getRealIndex(index))
-  const h = getGridCountForDate(monthDate)
+  const h = getGridCountForDate(monthDate, startWeekOnMonday)
   gridCounts[index] = h
   return h
 }
 
-export function getGridCountForDate(date: Date) {
+export function getGridCountForDate(date: Date, startWeekOnMonday: boolean) {
   const year = date.getFullYear()
   const month = date.getMonth()
   const daysInMonth = getDaysInMonth({ year, month })
-  const dayOfWeek = getFirstDayOfMonth({ year, month })
+  const dayOfWeek = getFirstDayOfMonth({ year, month, startWeekOnMonday })
   return Math.ceil((daysInMonth + dayOfWeek) / 7)
 }
 
diff --git a/src/__tests__/Date/CalendarHeader.test.tsx b/src/__tests__/Date/CalendarHeader.test.tsx
index 8fa1b4cb..e9601585 100644
--- a/src/__tests__/Date/CalendarHeader.test.tsx
+++ b/src/__tests__/Date/CalendarHeader.test.tsx
@@ -11,6 +11,7 @@ it('renders CalendarHeader', () => {
         onPrev={() => null}
         onNext={() => null}
         scrollMode={'vertical'}
+        startWeekOnMonday={false}
       />
     )
     .toJSON()
diff --git a/src/__tests__/Date/DayNames.test.tsx b/src/__tests__/Date/DayNames.test.tsx
index 1a16ed1f..c59e620c 100644
--- a/src/__tests__/Date/DayNames.test.tsx
+++ b/src/__tests__/Date/DayNames.test.tsx
@@ -4,7 +4,9 @@ import renderer from 'react-test-renderer'
 import DayNames from '../../Date/DayNames'
 
 it('renders DayNames', () => {
-  const tree = renderer.create(<DayNames locale={'en'} />).toJSON()
+  const tree = renderer
+    .create(<DayNames locale={'en'} startWeekOnMonday={false} />)
+    .toJSON()
 
   expect(tree).toMatchSnapshot()
 })
diff --git a/src/__tests__/Date/dateUtils.test.tsx b/src/__tests__/Date/dateUtils.test.tsx
index 3de4975e..165f27ea 100644
--- a/src/__tests__/Date/dateUtils.test.tsx
+++ b/src/__tests__/Date/dateUtils.test.tsx
@@ -73,10 +73,16 @@ describe('timeUtils', () => {
 
   it('should return correct gridCount for October 2021', () => {
     expect(
-      getGridCountForDate(addMonths(new Date(2018, 10 - 1, 1), 12 * 3))
+      getGridCountForDate(addMonths(new Date(2018, 10 - 1, 1), 12 * 3), false)
     ).toBe(6)
   })
 
+  it('should return correct gridCount for October 2021 with weeks starting on monday', () => {
+    expect(
+      getGridCountForDate(addMonths(new Date(2018, 10 - 1, 1), 12 * 3), true)
+    ).toBe(5)
+  })
+
   it('should get correct difference in month between dates', () => {
     expect(differenceInMonths(new Date(2022, 1, 1), new Date(2022, 2, 1))).toBe(
       1