The American series launched on July 5, 2000, on CBS and since the discontinuation of the Spanish version in 2022, is the longest-running adaptation in the Big Brother franchise.

The show broadly follows the premise of other versions, in which a group of contestants, known as "HouseGuests", live together in a specially constructed house that is isolated from the "Outside World" for a cash prize of $750,000 ($500,000 prior to season 23).

[11] The format of the series is viewed as a social experiment that requires HouseGuests to interact with others who may have differing ideals, beliefs, and prejudices.

[14][15] As of January 2025, there have been a total of 37 Showmances formed;[16] 11 of those that are still ongoing to date later took their relationships into the Outside World once a Big Brother season ended.

[note 1][21][22][23] While locked inside the House, the HouseGuests are free to quit the game for any unforeseen reason (also known as "walking"),[24] though they will not be allowed re-entry.

[31] There was also a "luxury challenge" that occurred in its 11th week, in which the HouseGuest who finds a lucky golden ticket would then be whisked away to attend the Primetime Emmy Awards.

After the nominations were finalized, the American public then had the opportunity to decide which HouseGuest should be evicted ("banished") through televoting, which lasted over the course of a full week.

[34][35][36][37] The Head of Household competition, introduced in season 2, is held at the beginning of each week and is most often occurred during the live eviction episode, unless otherwise specified.

[58][59] The winners of the first two rounds then get to participate in the final round; the winner there not only secures a spot in the Final Two, as well as being guaranteed at least the second place cash prize, but also gets to cast the sole eviction vote on one of the remaining two HouseGuests, since those two are nominated by default, automatically leaving the other in the House to prepare for a meeting with the Jury.

[71][72] Before the start of every Power of Veto competition, the current Head of Household and the two eviction nominees get to select three additional HouseGuests, thus bringing the total number of players to six, with the H.O.H.

This process continues until there are six HouseGuests left, in which they all get to play in the next Veto competition, which most often takes place in the live Double Eviction episode.

This changed in season 7 when they were forced to choose the players by a random "blind draw", pulling out either a ping-pong ball or flat disc, depending on the season, to reveal their choice; should one of them reveal a ball or disc that reads either "HouseGuest's Choice" or one of their own names, the player that drew it or got drawn on then gets to make the next available selection by word-of-mouth.

The holder then begins the meeting by explaining its power and ask for the two eviction nominees to give their final pleas, if they are allowed to do so.

The winner of that competition not only secures a spot in the Final Three but also gets to decide which HouseGuest will cast the sole vote to evict on one of the two nominees.

In the early seasons, the losers of a Have-Not competition would be placed on a peanut butter and jelly diet and would not be permitted to eat any other foods.

[76][77] Beginning in season 7, the losers were required to eat "Big Brother Slop" for food, and sleep in a special Have-Not room with cold showers and most discomforts such as hard pillows and beds for a week.

Actors such as Jeremy Piven,[93] David Hasselhoff,[94] and Neil Patrick Harris have all entered the house to participate in luxury competitions or rewards.

The Big Brother Jury, as stated above, plays a key role in voting for the winner of the season between the Final Two HouseGuests.

Many seasons have featured twists in which evicted HouseGuests (except for those who either walked or were expelled) can win re-entry into the House, either by a public vote or special competition.

Normally, this involves sequestering each evicted Houseguest individually or in the Jury House (depending on whether the twist occurred pre-Jury or post-Jury, respectively).

In an effort to promote diversity, CBS announced a new rule for Big Brother that 50% of all contestants must be BIPOC for the 2021–2022 broadcast season and from this point forward.

[115] The series, which lasted for thirty minutes and aired on weeknights, allowed fans to call in and discuss the events of the game.

Hosted by former Celebrity House Guests Marissa Jaret Winokur and Ross Mathews, the show aired on Fridays on Facebook following the live eviction;[128] however, it did not return for Big Brother 21.

In November 2023, CBS announced that there would be a special holiday spin-off called Big Brother Reindeer Games set to air for six days across two weeks starting on December 11, 2023.

[134][135] Though not actual spin-offs, both the English and French versions of Big Brother in Canada are, to date, the only franchises to fully adopt the American format;[136] the 2020 revival of Big Brother Australia also used the American format (in terms of nominations and evictions) but still relied on the Australian public to decide the eventual winner.

[151] The fourth season saw the release of a two-disc highlights DVD, featuring previously unseen footage deemed too racy for the main broadcast.

[162][163][164] In 2023, the live feeds launched on Pluto TV with limited commercial interruption, marking the first time they have been offered for free since the first season.

[165] Since its inception, Big Brother has been criticized following reports of "HIB" (Harassment, Intimidation and Bullying),[170] violence in the house, obscene language,[171][172][173][174] breach of integrity,[175][176] and the physical and mental strain of appearing on the series.

[178][179][180] On September 9, 2018, Chen's husband, Les Moonves, resigned as President of CBS after a second wave of reports of sexual misconduct allegations against him.

[181] Following her resignation from The Talk on September 18 after eight years as co-host, there was speculation on whether Chen would continue as host of Big Brother.