Yes. It is available 24 hours a day (except on Celebrity Xpedition Class ships) whether you want an extra blanket or a midnight snack. On all sailings, a late night room fee of $4.95 will be added to all orders received between 11pm and 6am. Room service outside the hours of 11pm and 6am is complimentary, although you may wish to offer a gratuity to room service staff.
Continental breakfast is served on request in your stateroom between 06:30am and 10:00am. A more extensive room service menu is available 24 hours a day on all sailings.