Lockout may mean:
- Lockout (industry), a work stoppage in which an employer prevents some or all employees from working
- Lockout (telecommunication), a system to prevent unwanted signals
- A daytime period in some hostels during which guests are disallowed from the premises
- A map for the video game Halo 2
- Lockout law, a law to prevent people entering venues between certain times, usually late at night as a crime prevention strategy
- Lockout-Tagout, a workplace safety system to prevent activation of machinery while a worker may be inside
- Regional lockout, a technological practice to prevent media use in a location other than that for which it is intended to be sold