Bill

The name Bill or Billy might refer to:
;Documents
* Bill (advertisement), an announcement for an entertainment event
* Bill (law), a law proposed or enacted by legislation
** Ferengi Bill of Opportunities
** Vulcan Bill of Rights
* Bill (payment), a type of invoice for monies owed
** Bar bill
** Bill of sale
** Medical bill
* "Clean bill of health", a phrase meaning one was healthy
;People
* Bill (Admiral), 23rd century Starfleet Fleet Admiral
* Bill (Borg), identity of a Borg drone, as identified by Magnus Hansen
* Billy (Carbon Creek), a resident of Carbon Creek in the 1950s
* Billy (Starfleet), an officer aboard the Enterprise NX-01
;See also: 
* William Claiborne, referred to as "Billy"
* William T. Riker, referred to, rarely, as "Bill" or "Billy"
* William Ross, referred to as "Bill"
* William Samuels, referred to as "Bill"
* William Telfer, referred to as "Billy"