diff --git a/packages/@mantine/dates/src/components/Day/Day.tsx b/packages/@mantine/dates/src/components/Day/Day.tsx
index d032934e90d..a8382a3c187 100644
--- a/packages/@mantine/dates/src/components/Day/Day.tsx
+++ b/packages/@mantine/dates/src/components/Day/Day.tsx
@@ -139,7 +139,7 @@ export const Day = factory<DayFactory>((_props, ref) => {
       unstyled={unstyled}
       {...others}
     >
-      {renderDay?.(date) || date.getDate()}
+      {renderDay?.(date) || dayjs(date).date()}
     </UnstyledButton>
   );
 });
diff --git a/packages/@mantine/dates/src/components/Month/Month.tsx b/packages/@mantine/dates/src/components/Month/Month.tsx
index af55c4e3eb2..b202701937b 100644
--- a/packages/@mantine/dates/src/components/Month/Month.tsx
+++ b/packages/@mantine/dates/src/components/Month/Month.tsx
@@ -23,7 +23,6 @@ import { getMonthDays } from './get-month-days/get-month-days';
 import { getWeekNumber } from './get-week-number/get-week-number';
 import { isAfterMinDate } from './is-after-min-date/is-after-min-date';
 import { isBeforeMaxDate } from './is-before-max-date/is-before-max-date';
-import { isSameMonth } from './is-same-month/is-same-month';
 import classes from './Month.module.css';
 
 export type MonthStylesNames =
@@ -216,7 +215,7 @@ export const Month = factory<MonthFactory>((_props, ref) => {
 
   const rows = dates.map((row, rowIndex) => {
     const cells = row.map((date, cellIndex) => {
-      const outside = !isSameMonth(date, month);
+      const outside = !dayjs(date).isSame(dayjs(month), 'month');
       const ariaLabel =
         getDayAriaLabel?.(date) ||
         dayjs(date)
diff --git a/packages/@mantine/dates/src/components/Month/get-date-in-tab-order/get-date-in-tab-order.ts b/packages/@mantine/dates/src/components/Month/get-date-in-tab-order/get-date-in-tab-order.ts
index 5e582fac387..8f5eff6ff6f 100644
--- a/packages/@mantine/dates/src/components/Month/get-date-in-tab-order/get-date-in-tab-order.ts
+++ b/packages/@mantine/dates/src/components/Month/get-date-in-tab-order/get-date-in-tab-order.ts
@@ -2,7 +2,6 @@ import dayjs from 'dayjs';
 import { DayProps } from '../../Day/Day';
 import { isAfterMinDate } from '../is-after-min-date/is-after-min-date';
 import { isBeforeMaxDate } from '../is-before-max-date/is-before-max-date';
-import { isSameMonth } from '../is-same-month/is-same-month';
 
 export function getDateInTabOrder(
   dates: Date[][],
@@ -21,7 +20,7 @@ export function getDateInTabOrder(
         isAfterMinDate(date, minDate) &&
         !excludeDate?.(date) &&
         !getDateControlProps?.(date)?.disabled &&
-        (!hideOutsideDates || isSameMonth(date, month))
+        (!hideOutsideDates || dayjs(date).isSame(dayjs(month), 'month'))
     );
 
   const selectedDate = enabledDates.find((date) => getDateControlProps?.(date)?.selected);
diff --git a/packages/@mantine/dates/src/components/Month/get-end-of-week/get-end-of-week.ts b/packages/@mantine/dates/src/components/Month/get-end-of-week/get-end-of-week.ts
index 14a22479b4c..2e1d9b46c6b 100644
--- a/packages/@mantine/dates/src/components/Month/get-end-of-week/get-end-of-week.ts
+++ b/packages/@mantine/dates/src/components/Month/get-end-of-week/get-end-of-week.ts
@@ -1,12 +1,13 @@
+import dayjs from 'dayjs';
 import type { DayOfWeek } from '../../../types';
 
 export function getEndOfWeek(date: Date, firstDayOfWeek: DayOfWeek = 1) {
-  const value = new Date(date);
-  const lastDayOfWeek = firstDayOfWeek === 0 ? 6 : firstDayOfWeek - 1;
+  let value = dayjs(date);
 
-  while (value.getDay() !== lastDayOfWeek) {
-    value.setDate(value.getDate() + 1);
+  const lastDayOfWeek = firstDayOfWeek === 0 ? 6 : firstDayOfWeek - 1;
+  while (value.day() !== lastDayOfWeek) {
+    value = value.add(1, 'day');
   }
 
-  return value;
+  return value.toDate();
 }
diff --git a/packages/@mantine/dates/src/components/Month/get-month-days/get-month-days.ts b/packages/@mantine/dates/src/components/Month/get-month-days/get-month-days.ts
index f48f7acc503..46575143077 100644
--- a/packages/@mantine/dates/src/components/Month/get-month-days/get-month-days.ts
+++ b/packages/@mantine/dates/src/components/Month/get-month-days/get-month-days.ts
@@ -1,3 +1,4 @@
+import dayjs from 'dayjs';
 import { DayOfWeek } from '../../../types';
 import { getEndOfWeek } from '../get-end-of-week/get-end-of-week';
 import { getStartOfWeek } from '../get-start-of-week/get-start-of-week';
@@ -13,9 +14,10 @@ export function getMonthDays({
   firstDayOfWeek = 1,
   consistentWeeks,
 }: GetMonthDaysInput): Date[][] {
-  const currentMonth = month.getMonth();
-  const startOfMonth = new Date(month.getFullYear(), currentMonth, 1);
-  const endOfMonth = new Date(month.getFullYear(), month.getMonth() + 1, 0);
+  const day = dayjs(month).subtract(dayjs(month).date() - 1, 'day');
+  const start = dayjs(day.format('YYYY-M-D'));
+  const startOfMonth = start.toDate();
+  const endOfMonth = start.add(+start.daysInMonth() - 1, 'day').toDate();
   const endDate = getEndOfWeek(endOfMonth, firstDayOfWeek);
   const date = getStartOfWeek(startOfMonth, firstDayOfWeek);
   const weeks: Date[][] = [];
diff --git a/packages/@mantine/dates/src/components/Month/get-start-of-week/get-start-of-week.ts b/packages/@mantine/dates/src/components/Month/get-start-of-week/get-start-of-week.ts
index 2bf51c5dc2e..13ba717a261 100644
--- a/packages/@mantine/dates/src/components/Month/get-start-of-week/get-start-of-week.ts
+++ b/packages/@mantine/dates/src/components/Month/get-start-of-week/get-start-of-week.ts
@@ -1,11 +1,11 @@
+import dayjs from 'dayjs';
 import type { DayOfWeek } from '../../../types';
 
 export function getStartOfWeek(date: Date, firstDayOfWeek: DayOfWeek = 1) {
-  const value = new Date(date);
-
-  while (value.getDay() !== firstDayOfWeek) {
-    value.setDate(value.getDate() - 1);
+  let value = dayjs(date);
+  while (value.day() !== firstDayOfWeek) {
+    value = value.subtract(1, 'day');
   }
 
-  return value;
+  return value.toDate();
 }
diff --git a/packages/@mantine/dates/src/components/Month/index.ts b/packages/@mantine/dates/src/components/Month/index.ts
index 19601bc6464..312e6ad3986 100644
--- a/packages/@mantine/dates/src/components/Month/index.ts
+++ b/packages/@mantine/dates/src/components/Month/index.ts
@@ -1,7 +1,6 @@
 export { getEndOfWeek } from './get-end-of-week/get-end-of-week';
 export { getStartOfWeek } from './get-start-of-week/get-start-of-week';
 export { getMonthDays } from './get-month-days/get-month-days';
-export { isSameMonth } from './is-same-month/is-same-month';
 
 export { Month } from './Month';
 export type { MonthProps, MonthSettings, MonthStylesNames, MonthFactory } from './Month';
diff --git a/packages/@mantine/dates/src/components/Month/is-same-month/is-same-month.test.ts b/packages/@mantine/dates/src/components/Month/is-same-month/is-same-month.test.ts
deleted file mode 100644
index dfa20b5e15a..00000000000
--- a/packages/@mantine/dates/src/components/Month/is-same-month/is-same-month.test.ts
+++ /dev/null
@@ -1,9 +0,0 @@
-import { isSameMonth } from './is-same-month';
-
-describe('@mantine/dates/is-same-month', () => {
-  it('detects same month', () => {
-    expect(isSameMonth(new Date(2021, 2, 1), new Date(2021, 2, 2))).toBe(true);
-    expect(isSameMonth(new Date(2021, 3, 1), new Date(2021, 2, 2))).toBe(false);
-    expect(isSameMonth(new Date(2022, 2, 2), new Date(2021, 2, 2))).toBe(false);
-  });
-});
diff --git a/packages/@mantine/dates/src/components/Month/is-same-month/is-same-month.ts b/packages/@mantine/dates/src/components/Month/is-same-month/is-same-month.ts
deleted file mode 100644
index 3391ec4ee99..00000000000
--- a/packages/@mantine/dates/src/components/Month/is-same-month/is-same-month.ts
+++ /dev/null
@@ -1,5 +0,0 @@
-export function isSameMonth(date: Date, comparison: Date) {
-  return (
-    date.getFullYear() === comparison.getFullYear() && date.getMonth() === comparison.getMonth()
-  );
-}