A mess hall is a place on Federation starships or starbases where one can relax and enjoy a meal or a quick snack in a social setting. It was an old Earth nautical term for the mass dining room for ships crew. It was also the place where officials, such as ambassadors of other worlds, were entertained. Gatherings were also held there, as it was often a relatively large space that had already been purposed for crew comfort.

The person in charge of activities within the mess hall held the title of mess officer.

On Intrepid-class vessels, the mess hall was on Deck 2, Section 13, with turbolift access in the corridor outside the starboard entrance. Some ships were equipped with four food replicators, with a private captain's dining room just behind the mess hall. The dining room could be reconfigured, and two of the replicators removed, to serve as a kitchen, as was done by Neelix aboard the USS Voyager.