The channel was officially announced by the Seven Network on its breakfast program, Sunrise, at 7:45 am AEDT 23 October 2009. Earlier, speculation suggested that Seven would launch its secondary channel around November 2009, with possible names including 7PLUS, PLUS7, Channel Mate and 7TWO. Seven's then-programming chief Tim Worner stated after the reveal that some of the potential names were red herrings to keep details of the channel a secret. PLUS7 and Channel Mate (as 7mate) were later used for Seven's internet TV catch-up service and Seven's second digital multi-channel respectively.
The channel launched with the airing of a promotional video called "Its Time", featuring Seven Network personalities and clips of shows and movies intended to be broadcast on the channel, followed by normal programming. This video was also launched on the multi-channel's website and received cross-promotion on the primary Seven channel. The Seven Network continues its policy of cross promoting each of their channel's content across all of its three channels to this day. Seven presenters Tom Williams and Johanna Griggs initially served as the "face" of the channel and were seen presenting 7TWO's Friday and Sunday night lifestyle line-ups in early 2011.
The channel did not launch on the same day to many regional areas. 7TWO was launched for Southern Cross Television viewers in Tasmania and Darwin on 1 December 2009, and for Prime Television viewers in Regional Victoria, Northern & Southern NSW and the ACT on 23 December 2009 from 9 am. From launch, Prime broadcast the channel as '7TWO on Prime'.
In January 2011, regional broadcaster Prime Television changed the name of its primary channel to 'Prime7', to reflect its strong relationship with its metropolitan partner, Seven. This led to Prime's re-transmission of 7TWO being rebranded as simply 7TWO, like the metropolitan counterpart.
From launch, premiere seasons of previous Seven shows including Lost, Ugly Betty, Heroes and 24 were broadcast, along with a mix of other new and classic programming along with movies sourced from Disney.
Prime-time programs used to screen under themed nightly blocks such as 'Action Time' and 'Movie Time', however these disappeared as the focus of the channel changed in 2010. The revised channel included 'Best of British' content such as thrice-weekly British murder/mystery (Heartbeat & Jonathan Creek), British comedy (Are You Being Served? & Keeping Up Appearances), and British lifestyle (Escape to the Country & Bargain Hunt). The launch of male-skewing sister channel, 7mate, in September 2010 led to a number of programs moving across from Seven's already existing channels, including 7TWO, to the new channel. 7TWO's target audience was also refined to people 55+. Programs that made the move from 7TWO included Air Crash Investigations, Scrubs, NWA: On Fire, Whacked Out Sports, Lost, Last Comic Standing, That '70s Show, AFL Game Day, Gary Unmarried, Club Reps, Fifth Gear, Monster Garage, and The Sopranos.
The weekday daytime schedule has seen numerous changes since launch as channel executives tried to find the right mix with viewers. At launch, 'Kid's Time' broadcast a block of children's programs each morning such as Count Duckula, and Power Rangers (now on GO!), soap operas aired in the early afternoon and 'Kitchen Time' featured in the late afternoons with Essence of Emeril and The Martha Stewart Show among the programs broadcast. In 2010, soap operas including Shortland Street, Coronation Street and, briefly, Emmerdale and Hollyoaks joined classic Australian soap Sons and Daughters and early years of Home and Away into its mid-morning schedule along with early episodes of quiz show Deal Or No Deal. In early afternoon, a mix of repeated fare such as Mistresses, Murphy Brown, Doctor Finlay, and movies from the Sony Pictures library are shown. Occasionally, shows which first-aired the previous night on the main Seven channel are encored on 7TWO during the day. While initially, dramas such as Grey's Anatomy were encored, more recently this has remained true only for Seven's local reality shows such as The X Factor and My Kitchen Rules. An early morning weekly omnibus of the previous week's new episodes of Home and Away airs on Sundays.
The Seven Network introduced new blocks of children's programming to both 7TWO and its 'brother' channel, 7mate, in 2012 with female-skewing series such as Hannah Montana and Wizards of Waverly Place airing on 7TWO between 7-9 am. The 7TWO block was replaced by local Australian children's programs in 2013. From 2012 to 2016 on Saturdays at 7 am, Saturday Disney switched to 7TWO for its last two hours shown while Seven broadcast Weekend Sunrise, later moving to 7flix in 2016 until its end.
A library of classic films are broadcast on 7TWO, sourced from Sony Pictures, Rank Arena and RKO Radio Pictures.
By the end of Summer 2010/11, 7TWO had proven itself to become the most watched multi-channel in the country dominating primetime slots with a total 6.4% audience share via the network across the 5 major cities and winning 9 weeks over GO!'s two weeks (one joint with 7TWO) which is largely attributed to the channel's increased broadcast of British-originated content across the week. In 2011, following GO!'s ratings share success (for digital channels) in 2010, 7TWO has stolen their crown as the number one multi-channel and the number one most-watched multichannel of the decade and century in Australia.
From launch until early 2013, 7TWO re-aired all daytime and prime-time national Seven News updates, no more than two commercial breaks after their original broadcast on the main Seven channel. These were all produced in Seven's Sydney news studio and hosted by either newsreader Chris Bath or Mark Ferguson.
On 5 August 2013, a national news bulletin began airing on 7TWO, titled Seven News at 7, airing at 7:00 pm Monday to Friday. It was presented by Melissa Doyle, with David Brown on weather. Many months after the Nine Network's rival 7 pm bulletin on GEM had ended, 7TWO aired their last Seven News At 7 bulletin on 2 May 2014.
7TWO televised live coverage of tennis tournament Wimbledon for the first time in 2011, first going to air at 8:30 pm AEST on 7TWO whilst the primary channel continued normal programming before switching over to Seven at around 10.30 pm. This practice has continued each year since.
From January 2012, 7TWO has started broadcasting smaller tennis tournaments from Seven's Summer of Tennis, including the Brisbane International, Sydney International and AAMI Classic. This has allowed Seven's main channel to continue with normal programming.
Further sports coverage on 7TWO includes Horse Racing and Davis Cup tennis. 7TWO is also used to continue Seven's coverage of sport when the main Seven channel breaks for its nightly news bulletin such as with the Australian Open tennis.
In 2010, 7TWO broadcast classic AFL and Australian Open tennis matches from the Seven archives between midnight and dawn.
In August 2016, 7TWO broadcast the 2016 Summer Olympic Games and 2016 Summer Paralympics from Rio de Janeiro in September.
7TWO is available in standard definition digital in metropolitan areas and regional Queensland through Seven Network owned-and-operated stations including ATN Sydney, HSV Melbourne, BTQ Brisbane, SAS Adelaide, TVW Perth and STQ Queensland. As well as this, Southern Cross Television rebroadcast the service through TNT Tasmania and TND Darwin. Regional affiliate Prime7 (Regional NSW/ACT and VIC) also broadcasts 7TWO, launching on 23 December 2009. WIN Television Griffith launched 7Two on 5 June 2012, the day of the analogue switch off. Southern Cross Television (Regional SA, Central) began broadcasting in January 2012 and GWN7 (Regional WA) soon followed.