Rosamunde Scott was born on 22 September 1924 in Lelant, Cornwall, England, UK, daughter of Helen and Charles Scott, a British commander. Just before her birth her father was posted in Burma, her mother remained in England. She attended St. Clares Polwithen and Howells School Llandaff before going on to Miss Kerr-Sanders Secretarial College. She began writing when she was seven, and published her first short story when she was 18. From 1943 through 1946, Pilcher served with the Womens Naval Service. On 7 December 1946, she married Graham Hope Pilcher, a war hero and jute industry executive who died in March 2009. They moved to Dundee, Scotland, where she still lives today with a dog in Perthshire. They had two daughters and two sons, and fourteen grandchildren. Her son, , is also a novelist.

In 1949, her first book, a romance novel, was published by Mills & Boon, under the pseudonym . She published a further ten novels under that name. In 1955, she also began writing under her married name Rosamunde Pilcher, by 1965 she her own name to all of her novels. In 1996, her novel Coming Home won the Romantic Novel of the Year Award by Romantic Novelists Association. She retired from writing in 2000. Two years later, she was named an Officer of the Order of the British Empire (OBE).