By or BY may refer to:
Places
- By, Doubs, France, a commune
- By, Norway, a village
Codes
- Belarus ISO country code
- .by, country-code top-level domain for Belarus
- Burundi, obsolete FIPS Pub 10-4 and NATO digram country codes
- TUI Airways (IATA code: BY), formerly Thomson Airways, Thomsonfly and Britannia Airways
Other uses
- By Saam (1914–2000), American sports announcer
- John By (1779–1836), British military engineer famous for his work in Canada
- CC BY, a Creative Commons attribution license
- Budget year, a synonym for fiscal year
- B-Y, blue-luminance difference in color
See also
- -by, a common suffix for settlements in northern England
- Beye
- Bye (disambiguation)
- Buy (disambiguation)
- Bie (disambiguation)
- BI (disambiguation)