diff --git a/src/LocalDateTime.php b/src/LocalDateTime.php
index 2a2727a..62c159d 100644
--- a/src/LocalDateTime.php
+++ b/src/LocalDateTime.php
@@ -31,17 +31,17 @@ public function __construct(
     }
 
     /**
-     * @param int $year   The year, from MIN_YEAR to MAX_YEAR.
-     * @param int $month  The month-of-year, from 1 (January) to 12 (December).
-     * @param int $day    The day-of-month, from 1 to 31.
-     * @param int $hour   The hour-of-day, from 0 to 23.
-     * @param int $minute The minute-of-hour, from 0 to 59.
-     * @param int $second The second-of-minute, from 0 to 59.
-     * @param int $nano   The nano-of-second, from 0 to 999,999,999.
+     * @param int       $year   The year, from MIN_YEAR to MAX_YEAR.
+     * @param int|Month $month  The month-of-year, from 1 (January) to 12 (December).
+     * @param int       $day    The day-of-month, from 1 to 31.
+     * @param int       $hour   The hour-of-day, from 0 to 23.
+     * @param int       $minute The minute-of-hour, from 0 to 59.
+     * @param int       $second The second-of-minute, from 0 to 59.
+     * @param int       $nano   The nano-of-second, from 0 to 999,999,999.
      *
      * @throws DateTimeException If the date or time is not valid.
      */
-    public static function of(int $year, int $month, int $day, int $hour = 0, int $minute = 0, int $second = 0, int $nano = 0): LocalDateTime
+    public static function of(int $year, Month|int $month, int $day, int $hour = 0, int $minute = 0, int $second = 0, int $nano = 0): LocalDateTime
     {
         $date = LocalDate::of($year, $month, $day);
         $time = LocalTime::of($hour, $minute, $second, $nano);
@@ -306,7 +306,7 @@ public function withYear(int $year): LocalDateTime
      *
      * @throws DateTimeException If the month is invalid.
      */
-    public function withMonth(int $month): LocalDateTime
+    public function withMonth(Month|int $month): LocalDateTime
     {
         $date = $this->date->withMonth($month);
 
diff --git a/src/ZonedDateTime.php b/src/ZonedDateTime.php
index be3682d..d62c28c 100644
--- a/src/ZonedDateTime.php
+++ b/src/ZonedDateTime.php
@@ -347,7 +347,7 @@ public function withYear(int $year): ZonedDateTime
     /**
      * Returns a copy of this ZonedDateTime with the month-of-year altered.
      */
-    public function withMonth(int $month): ZonedDateTime
+    public function withMonth(Month|int $month): ZonedDateTime
     {
         return ZonedDateTime::of($this->localDateTime->withMonth($month), $this->timeZone);
     }
diff --git a/tests/LocalDateTimeTest.php b/tests/LocalDateTimeTest.php
index 1d1dae8..beb5c30 100644
--- a/tests/LocalDateTimeTest.php
+++ b/tests/LocalDateTimeTest.php
@@ -13,6 +13,7 @@
 use Brick\DateTime\LocalDate;
 use Brick\DateTime\LocalDateTime;
 use Brick\DateTime\LocalTime;
+use Brick\DateTime\Month;
 use Brick\DateTime\Parser\DateTimeParseException;
 use Brick\DateTime\Period;
 use Brick\DateTime\TimeZone;
@@ -32,9 +33,12 @@ class LocalDateTimeTest extends AbstractTestCase
 {
     public function testOf(): void
     {
-        $date = LocalDate::of(2001, 12, 23);
         $time = LocalTime::of(12, 34, 56, 987654321);
 
+        $date = LocalDate::of(2001, 12, 23);
+        self::assertLocalDateTimeIs(2001, 12, 23, 12, 34, 56, 987654321, new LocalDateTime($date, $time));
+
+        $date = LocalDate::of(2001, Month::DECEMBER, 23);
         self::assertLocalDateTimeIs(2001, 12, 23, 12, 34, 56, 987654321, new LocalDateTime($date, $time));
     }
 
@@ -349,10 +353,13 @@ public static function providerWithInvalidYearThrowsException(): array
     #[DataProvider('providerWithMonth')]
     public function testWithMonth(int $year, int $month, int $day, int $newMonth, int $expectedDay): void
     {
-        $date = LocalDate::of($year, $month, $day);
         $time = LocalTime::of(1, 2, 3, 123456789);
-        $localDateTime = $date->atTime($time)->withMonth($newMonth);
-        self::assertLocalDateTimeIs($year, $newMonth, $expectedDay, 1, 2, 3, 123456789, $localDateTime);
+
+        $date = LocalDate::of($year, $month, $day);
+        self::assertLocalDateTimeIs($year, $newMonth, $expectedDay, 1, 2, 3, 123456789, $date->atTime($time)->withMonth($newMonth));
+
+        $date = LocalDate::of($year, Month::from($month), $day);
+        self::assertLocalDateTimeIs($year, $newMonth, $expectedDay, 1, 2, 3, 123456789, $date->atTime($time)->withMonth($newMonth));
     }
 
     public static function providerWithMonth(): array
diff --git a/tests/ZonedDateTimeTest.php b/tests/ZonedDateTimeTest.php
index 3f859a3..cc61a23 100644
--- a/tests/ZonedDateTimeTest.php
+++ b/tests/ZonedDateTimeTest.php
@@ -12,6 +12,7 @@
 use Brick\DateTime\LocalDate;
 use Brick\DateTime\LocalDateTime;
 use Brick\DateTime\LocalTime;
+use Brick\DateTime\Month;
 use Brick\DateTime\Parser\DateTimeParseException;
 use Brick\DateTime\Period;
 use Brick\DateTime\TimeZone;
@@ -581,6 +582,7 @@ public function testWithYear(): void
     public function testWithMonth(): void
     {
         self::assertIs(ZonedDateTime::class, '2000-07-20T12:34:56.123456789-07:00[America/Los_Angeles]', $this->getTestZonedDateTime()->withMonth(7));
+        self::assertIs(ZonedDateTime::class, '2000-07-20T12:34:56.123456789-07:00[America/Los_Angeles]', $this->getTestZonedDateTime()->withMonth(Month::JULY));
     }
 
     public function testWithDay(): void