| Voice: | Contralto |
| Nationality: | English |
| Year of Birth: | Not entered yet. |
| Year of Death: | 1931 |
Bertha Amy Lewis (12 May 1887 – 8 May 1931) was an English opera singer and actress primarily known for her work as principal contralto in the Gilbert and Sullivan comic operas with the D'Oyly Carte Opera Company.
Lewis was born in Forest Gate, London. She attended St. Angela's High School, Upton and then studied voice at the Royal Academy of Music, gaining an A.R.A.M. qualification. She had made professional appearances on the concert stage but had not acted before she joined D'Oyly Carte at the age of 19 in 1906 as Kate in The Pirates of Penzance. She soon was touring with the company as Kate, Lady Saphir in Patience, Leila in Iolanthe, Ada in Princess Ida, Vittoria in The Gondoliers, and First Bridesmaid in Trial by Jury. In 1908, at the Savoy Theatre, she played the part of Gwenny Davis in Fenn and Faraday's A Welsh Sunset, a curtain raiser to H.M.S. Pinafore. She soon added to her repertoire Leila in Iolanthe and Inez in The Gondoliers.
In 1909 she replaced Ethel Morrison as principal contralto, playing Little Buttercup in H.M.S. Pinafore, Ruth in Pirates, Lady Jane in Patience, the Queen of the Fairies in Iolanthe, Lady Blanche in Princess Ida, Katisha in The Mikado, Dame Carruthers in The Yeomen of the Guard, and the Duchess of Plaza-Toro in The Gondoliers. In 1910 she married the baritone Herbert Heyner; in the same year she left the company to tour the UK in concerts and grand opera, appearing in the title role of Bizet's Carmen, as Delilah in Camille Saint-Saëns's Samson and Delilah, and as Amneris in Verdi's Aida.