Filby is a surname derived from locality Filby. Notable people with the surname include:
Eric Filby (1917–2004), English table tennis and lawn tennis player Ian Filby (born 1954), English football forward William Filby (Roman Catholic priest) (–1582), Roman Catholic priest and martyr in medieval England William Filby (Anglican priest) (1933–2009), Anglican priest
See also Philby, a surname