In broadcasting, the watershed (or safe harbor) is the time of day after which programming with content deemed suitable only for mature or adult audiences is permitted. In the same way that a geological watershed divides two drainage basins, a broadcasting watershed serves as a dividing line in a schedule between family-friendly content and content deemed suitable only for a more mature audience, such as programs containing objectionable content; this can include graphic violence, strong language, and sexual content, or strong references to those themes, even if they are not shown explicitly. Many countries expect or require the transition to more adult material to not be abrupt, with the more 'mature' material appearing only later in the evening. The degree to which the watershed is publicly discussed and referred to also varies by country and culture; for English, in the United Kingdom and Commonwealth it is common to refer to programming as watershed or pre-watershed, while in the United States referring to a program as in the safe harbor is industry jargon general audiences will usually not understand.

In some countries, watersheds are enforced by broadcasting laws. Cultural differences around the world allow those watershed times to vary. For instance, in Australia, the watershed time is 19:30 (7:30 p.m.), and in Italy it is 22:30 (10:30 p.m.). In some countries, the schedule is divided into periods with progressively fewer restrictions. In addition, some countries are more lenient towards subscription television and radio or pay-per-view channels than towards free-to-air channels.

By country Argentina In Argentina, any programmes broadcast between 06:00 or 07:00 and 22:00 or 22:30 must be suitable for all ages. There are also three other ratings, SAM 13, SAM 16, and SAM 18, which may be broadcast only during the broadcast time that is not covered by any programme suitable for family viewing.

Starting in September 2010, broadcasters must show the notices "Comienza el horario apto para todo público" () and "Finaliza el horario apto para todo público" () at 6:00 a.m. or 7:00 a.m. and 10:00 p.m. or 10:30 p.m. respectively. In addition, the notice "Atención: Contenido no apto para niños, niñas y adolescentes" () is shown before news broadcasts.

Australia On Australian television, programmes are restricted to certain times based on their rating. Since December 2015, PG-rated programmes can be shown at any time of day, M-rated programmes from 19:30, and MA15+ programmes from 20:30. M-rated programmes can also be shown from 12:00 to 15:00 on school days.

Complications with Australian time zones allow that to vary slightly in some areas. For example, when daylight saving time is in effect in New South Wales, NSW-based stations broadcasting to the Gold Coast, Queensland, would effectively push the broadcast watersheds an hour earlier, as Queensland does not observe DST; however, complaints by Gold Coast residents have forced those stations to delay prime-time programming by one hour to compensate.

With the exception of subscription narrowcast channels, anything rated R18+ must not be shown on Australian television at any time, and must be edited to fit within MA15+ guidelines. Even on subscription narrowcast channels, the owner of the channel must ensure that its content is restricted to access by those with appropriate disabling devices.

Austria There is no legally binding watershed in Austria. However, according to its regulations, the public service broadcaster's channels do not air content that might harm the physical, mental or moral development of minors before 8:15 p.m. and when fictional programmes "not suitable for children" or "only for adults" are aired, an X or O, respectively, is added to the digital on-screen graphic.

Brazil

In Brazil, the concept of watershed was officially abolished on August 31, 2016, after a decision made by the Supreme Federal Court (Supremo Tribunal Federal). Despite online activism organized by some opposing parents and critics, such as Helena Martins, a journalist and representative of the National Program of Human Rights (Programa Nacional de Direitos Humanos), who created a petition on the Internet trying to prevent the decision, the Court ruled in favor of a lawsuit made by the Brazilian Labor Party (Partido Trabalhista Brasileiro), which received the support (during the lawsuit) of the Brazilian Association of Radio and Television Broadcasters (Associação Brasileira de Emissoras de Rádio e Televisão), composed of a group of several radio and television broadcasters spread throughout the country. Both organizations advocated for the national abolition of the watershed, claiming that the watershed was a kind of restriction that caused problems related to the "lack of programming freedom" on the Brazilian television.

Starting in 1990, when the Advisory Rating Coordination (Coordenação de Classificação Indicativa) of the Department of Justice Politics (Departamento de Políticas de Justiça) was established, until the August 31, 2016 Supreme Court ruling, the Brazilian advisory rating system determined not only the content rating of a program, but also imposed a watershed system, who was created in line with the Child and Adolescent Statute (Estatuto da Criança e do Adolescente), a series of regulations who determine what are the children's rights in Brazil. The watershed was composed by the following rules:

Programs rated L (Free for All AudiencesLivre para Todos os Públicos), 6 (Not recommended for minors under 6Não recomendado para menores de 6 anos), and 10 (Not recommended for minors under 10Não recomendado para menores de 10 anos) could be broadcast at anytime; Programs rated 12 (Not recommended for minors under 12Não recomendado para menores de 12 anos) could be broadcast only between 8:00p.m. (20:00) and 6:00a.m.; Programs rated 14 (Not recommended for minors under 14Não recomendado para menores de 14 anos) could be broadcast only between 9:00p.m. (21:00) and 6:00a.m.; Programs rated 16 (Not recommended for minors under 16Não recomendado para menores de 16 anos) could be broadcast only between 10:00p.m. (22:00) and 6:00a.m.; Programs rated 18 (Not recommended for minors under 18Não recomendado para menores de 18 anos) could be broadcast only between 11:00p.m. (23:00) and 6:00a.m.

The watershed was enforced only for free-to-air television channels (both VHF and UHF); pay television channels were not required to follow the watershed, and indeed, could broadcast any program anytime.

Before 1990, during the military dictatorship and in the early New Republic, the regulator entity for the watershed was the Public Diversions Censorship Division (Divisão de Censura de Diversões Públicas) of the Federal Police of Brazil (Polícia Federal do Brasil). More known simply as the "Federal Censorship" (Censura Federal), it was this division who determined if a pre-recorded television program was eligible to be transmitted on a determined time (the Censorship Division also decided what was the content rating of these programs, and had the power to impede the broadcast of unauthorized programs, meaning that all television programs that were not broadcast live had to be previously sent to the "Federal Censorship" through videotapes to receive the authorization of transmission before they could be aired).

Canada Content on commercial broadcasters in Canada is self-regulated by the Canadian Broadcast Standards Council (CBSC) under the CAB Code of Ethics and Violence Code. The state-owned Canadian Broadcasting Corporation (CBC) is required to follow the Violence Code as a condition of license, with enforcement handled via the Canadian Radio-television and Telecommunications Commission (CRTC).

The CBSC codes specify that broadcasters may not air programming that contains sexually explicit material or offensive language intended for adult audiences outside of the "late viewing period," which is defined as programming beginning at 9:00 p.m., and ending at 5:30 a.m. Programs that begin before 9:00 p.m. are considered pre-watershed even if they run into this time period. The watershed is based on the time zone from which the signal originates. 11:00 p.m. is the watershed for radio broadcasting; before then and after 4:00 a.m., radio stations are forbidden from broadcasting content that glorifies violence, undue coarse language, or undue sexually explicit material.

The Violence Code does provide some leniency for scheduling programs pre-watershed in order to exercise a terrestrial broadcaster's simsub rights (acknowledging that content advisories are also mandated by the code). However, in any case, no broadcaster may air material that contains "gratuitous violence in any form or which sanctions, promotes or glamourizes violence."

Chile In Chile, prior to the establishment of content rating systems in 1993, watershed was the only way that television networks used to separate adult programs from the rest of the schedule. Back then, adult programming could only air after 21:30 (which, on most networks, coincided with the end of prime-time newscasts). It was later moved to 22:00. The Consejo Nacional de Televisión requires all networks (even pay TV channels based in Chile) to broadcast a warning shortly before the watershed (either as a standalone ident or as a lower-third); if they skip the warning, they risk facing a fine. Broadcasting the warning late also results in a fine, with TV+ receiving one in December 2020. The adult-programming period ends at 6:00 (though most networks ended it right after sign-off, as 24/7 stations weren't common prior to 2022).

In April 2024, the CNTV's president, Mauricio Muñoz, revealed in an interview that the Asociación Nacional de Televisión, the Defensoría de la Niñez and other institutions solicited the regulator to move the watershed from 22:00 to 21:00. Reasons for the change included sleep-related health issues on children with the old watershed, and prime-time newscasts becoming more violent and crime-focused. The proposal was approved on 10 October 2024, though it was said it would only be moved once it was published on the Diario Oficial. The watershed was officially moved on 5 November 2024.

Czech Republic In the Czech Republic, only programmes that "can be watched by children" can be aired until 22:00. After 22:00, adult-oriented programmes may be aired. They had to be marked with star on either corner of image. Notably Czech Television stations (ČT1 and ČT2) were among to include this logo until 2007.

Finland

In Finland, all the major television companies (Yle, MTV Media, Nelonen Media, SBS Finland and Fox International) have agreed not to show 16-rated content before 21:00 and 18-rated content before 23:00. Television channels use their own discretion to decide the ratings. Before airing a programme, the channel must provide the related rating information to the governmental bureau Finnish Centre for Media Education and Audiovisual Media,"Televisioyhtiöiden käytännesäännöt" , Finnish Centre for Media Education and Audiovisual Media, 2007. Retrieved on 2012-09-07. which replaced the now-defunct Finnish Board of Film Classification in that capacity in early 2012.

France

In France, -12 rated programmes/films are not allowed before 22:00, and -16/-18 rated programmes/films are not allowed before 22:30 and 00:00 respectively. -18 rated programmes/films may air only via satellite and cable. The period in which programmes with any ratings are permitted finishes at 06:00 except for -18 programmes, which may not be issued after 05:00.