PHP Manual Function Reference Date and Time Related Extensions Date/Time DateTimeImmutable DateTimeImmutable::setDate DateTimeImmutable::__set_state DateTimeImmutable::setISODate DateTimeImmutable::setDate (PHP 5 >= 5.5.0)DateTimeImmutable::setDate — Sets the date Description public DateTimeImmutable DateTimeImmutable::setDate ( int $year , int $month , int $day ) Like DateTime::setDate() but works with DateTimeImmutable.