Rundell spent much of her widowhood travelling, staying for periods with family and close friends, as well as abroad. Rundell's son, Edmund Waller Rundell, joined the well-known jewellers and goldsmiths Rundell and Bridge; the firm was run by Philip Rundell, a relation of Maria Rundell's late husband. Edmund later became a partner within the firm. In 1827, Philip died; he left Maria £20,000, and £10,000 each to Edmund and Edmund's wife. In 1828, Rundell travelled to Switzerland. She died in Lausanne on 16 December.
