ABY is a three-letter acronym that may refer to:
- Archbishop of York, a senior post in the Church of England
- Aby, a village in Lincolnshire, England
- "After the Battle of Yavin", a system of measuring dates in Star Wars. For more information, see The Star Wars Wiki article Galactic Standard Calendar.
- Ashburys railway station in the United Kingdom, from its National Rail code
- Southwest Georgia Regional Airport in Albany, Georgia, United States, from its IATA airport code
- Abyssinian cat, a shorthair cat breed