After returning to Barcelona in 1890 Granados spent the next decade building a dual career as pianist and composer, forming a successful piano trio with Belgian violinist Crickboom and the young Pablo Casals. His first opera, Maria del Carmen, was well received at its premiere in 1898, after which the Order of Carlos III (a Spanish knighthood) was bestowed upon Granados by a supportive government. Granados was quick to follow up on this success, and two more operas were produced in the next five years.

For the 1900 season Granados founded the Society of Classical Concerts (Sociedad de Conciertos Clásicos) in Barcelona, which, although short-lived, gave him the confidence to create his own piano school the following year (known as the Granados School, or Academia Granados). The school was a success, and Granados maintained his involvement with it until his death.

Granados was one of the great pianists of the late nineteenth and early twentieth centuries. Virtually all his music relies heavily on the Catalan and Spanish folk idiom (e.g. Twelve Spanish Pieces, or Six Pieces on Spanish Popular Songs), which, along with fellow Spaniard Isaac Albéniz, Granados was instrumental in bringing to the attention of the contemporary European musical establishment. Goyescas, begun in 1902 but not finished until 1911, is perhaps his mightiest achievement. (Granados also produced an opera by the same name -- both the pianistic and operatic incarnations of the work take the striking visuals of Goya as their inspiration.)

In 1916, while returning from the U.S.A. (where the opera Goyescas had received a New York premiere on January 26, 1916, and where Granados had performed in the White House for President Wilson), the liner Sussex was torpedoed by a German U-boat. Among the casualties were Granados and his wife of 24 years.