O'Mara and his wife returned to London for a series of concert engagements, but in the Autumn of 1897, they travelled again to America where O'Mara created the tenor lead in Reginald De Koven's "The Highwayman." O'Mara gave many private concerts at the beginning of the new century, but happily returned to opera as leading tenor with the Moody-Manners Opera Company in London from 1902 to 1908, performing in "Maritana", "Cavalleria", "Faust", "Lohengrin", "Pagliacci", "Il trovatore", "Carmen", Charles Gounod's "Roméo et Juliette", and the first English-language production of Puccini's "Madame Butterfly" (1907), also performing extensively in Ireland with the company. O'Mara was granted the Freedom of the City of Limerick in 1908, the only time that a singer achieved this honour.