An Grianán Theatre is a flagship venue and an integral part of the cultural life of County Donegal. The spacious auditorium has a seating capacity of 345. This dramatic space is also available for use as a corporate venue, offering excellent technical and catering facilities. In addition, a full range of projection equipment is available.

The café is open all day, serving full meals, snacks and coffee. A full bar service is available before and after each performance. An Grianán has full facilities for people with disabilities including designated seating in the auditorium, lift and specially adapted W.C. There is also an inductive loop hearing system.

There is ample and spacious parking to the rear of the theatre, for both cars and coaches. The theatre provides dressing rooms, workshops and a spacious green room for visiting performers.