The theatre has a capacity of 1,144,[1] and hosts a number of touring productions including musicals, plays and children's shows and also presents an annual Christmas pantomime.

The building was designed by the London-based theatre architects Ernest Runtz and Ford and constructed from brick and Bath Stone.

Structural alterations to accommodate projectors, sound equipment and a large screen were made and for the next four years it was used mainly as a cinema, with the occasional live show.

[8] The artists that have performed on stage at the New Theatre have included Sarah Bernhardt, Anna Pavlova, Laurel and Hardy, Tom Jones, Tommy Cooper, Tessie O'Shea and Shirley Bassey.

[11] In 1954 Welsh National Opera made the New Theatre its home and principal base, however they have subsequently moved and taken up permanent residence in Wales Millennium Centre.

[14] Following the Covid 19 pandemic, the theatre re-opened in September 2021, after the longest closure in its history, with a week-long run of Priscilla, Queen of the Desert.

New Theatre re-opened again at the end of January 2022 with the concert A Beautiful Noise, followed by near-capacity performances of musicals The Rocky Horror Show and Hairspray.