The general concept for GO! was revealed on 23 March 2009, with the Nine Network announcing their intention to start a standard definition variety-based multichannel, launched midway through 2009. The channel's name and branding was first revealed as GO!99 on 14 April 2009 by TV Tonight, a blog dedicated to Australian television.
The channel's final name was confirmed by the Nine Network via A Current Affair as GO! on 15 July 2009, as well as multi-coloured logo variations.
The channel went to air at 1:00 pm on 5 August 2009, broadcasting a promo loop. GO! officially began broadcasting scheduled programming from 9 August 2009 at 6:30 pm with a 1-minute promo featuring the song "Go!" by Sydney based sound house group Noise International featuring vocals by Sharon Muscat. It was then followed by an episode of Wipeout, the first programme to air on the new channel.
The Nine Network's regional affiliates, WIN Television and NBN Television, also launched GO! on 9 August 2009, on channel 88.
Darwin received the channel in October 2010 (over a year after other capital cities started transmitting the multi channel). From December 2010, Nine Network affiliate Imparja Television commenced transmission of the GO! channel to viewers in remote areas of Central, Northern and Eastern Australia, before expanding to Eastern South Australia on 11 November 2011.
There have been reports that GO!'s technical launch had caused a significant number of digital TV receivers to no longer pick up Nine's digital channels. Nine have established a helpline for viewers experiencing problems or requiring assistance to tune in to the new channel.
The theme song, "Go" by Noise International featuring Sharon Muscat was later released on iTunes in the same year that it launched (2009). A music video for the song was shown on GO! after programs featuring Sharon Muscat performing the song with a dancing crowd.
GO! celebrated its first birthday in 2010 by playing movies every night at 10pm during the month of August 2010. GO! also played a mini clip during the commercial breaks thanking everyone for watching GO!
GO! introduced Newsbursts, a news-break filler program in 2010. These would usually feature a breaking news story and the weather. These were later dropped in 2011, replaced by repeats of Nine's Newsbreak.
GO! received a new on-air presentation for 2011. GO! also played a mini clip after programs during Summer 2010/2011, featuring the song "Hello" by The Potbelleez, saying that 2011 was going to be a great year for GO! with the slogan "Let's GO! 2011". This presentation remained unchanged for the next few years (Except for the lineup, which was updated in 2013 but not the rest).
On 27 January 2014, GO! stopped using the Supertext logo and switched to Nine's Closed Captioning logo.
On 2 February 2014, GO! received a new logo, new on-air presentation graphics updated by creative company DD8, a new demographic, and a revamped lineup, with Kids WB having a Weekday version.
The channel was also changed to a Youth-organised channel, with most of the daytime lineup having Kids programming, and most of the nighttime programming being Movies and Youth-Adult programming.
On 26 November 2015, the Nine Network introduced a network-wide rebrand of all of its digital channels with GO! being renamed 9Go!. Additionally, 9Go! was moved to channel 93, but a simulcast currently remains available on channel 99. Later, 9Go!'s on-air theme was changed for a continuous design across all of its channels. This included a new look for program listings, program advertisements and promos.
Nine announced that it had signed a new affiliation deal with Southern Cross Austereo on 29 April 2016, replacing WIN Television as the primary Nine affiliate starting 1 July 2016. Consequently, 9Go! will be broadcast by Southern Cross into Regional Queensland, Southern NSW/ACT, Regional Victoria and Spencer Gulf SA/Broken Hill NSW on channel 53.
On 21 September 2016, 9Go! announced their 100 Days of Movie Event Bigness, which ran during primetime from 30 September 2016 to 8 January 2017, starting with airings of The Spiderwick Chronicles and The Hobbit: An Unexpected Journey.
On 12 December 2016, 9Go!'s daytime schedule because a part-time channel called Go! Kids, leading into 9Go! only being broadcast nightly, akin to the ABC multichannel ABC2, who broadcasts little kids shows under the ABC Kids branding from 5am to 7pm.
Original plans for GO! suggested it would consist of a mix of entertainment and lifestyle programming (this rule wasn't featured until the launch of future Female-oriented HD channel GEM in 2010). However, this branding was replaced by a youth-orientated light-entertainment channel instead. GO!'s programming is generally structured under nightly themed blocks, which consists of comedy on Sunday, all new reality shows on Tuesday, sci-fi on Wednesday, female-skewed drama on Thursday (until the launch of GEM, when it was replaced by Movies themings instead), and movies on Friday. Movies screen with "limited and brief commercial breaks". The schedule is designed not to cannibalise viewers from the main Nine channel.
It was announced in June 2009 that the Nine Network had signed a $500 million deal with Warner Bros. to continue its current output deal for another five years from 2011 to 2015. The deal helped Nine retain existing content (including many television series and films), as well as providing new content for both its primary channel, GEM (launched in 2010) and Go!. The network also has ongoing content deals with Columbia Pictures and Village Roadshow, and has secured a new content partnership with MTV Networks.
Feature classic films broadcast on 9Go! are sourced from its studio-output deals, including 20th Century Fox, DreamWorks, DreamWorks Animation, Lions Gate, Metro-Goldwyn-Mayer, Paramount Pictures and Warner Bros. (old films only).
Leading up to the ad break, GO! airs replays of Nine's Newsbreak that air on the main Nine channel and from GEM. All newsbreaks are broadcast across any state. The NRL is shown on GO! in Melbourne, Adelaide, Perth and Tasmania on Friday nights when the cricket is scheduled on GEM.South Beach Tow
NRL matches were shown on 9Go! on Friday nights if the cricket was scheduled on 9Gem in Victoria, Tasmania, South Australia and Western Australia. 9Go! also broadcast the 2015 Liverpool FC tour matches against Brisbane Roar and Adelaide United. The NBL was broadcast on 9Go! on Sundays if the cricket was scheduled on 9Gem.
9Go! is available in standard definition in metropolitan areas through Nine Network owned-and-operated stations: TCN Sydney, GTV Melbourne, QTQ Brisbane, NWS Adelaide, STW Perth and NTD Darwin, as well as NBN Television station in Northern NSW and other stations CTC Southern NSW/ACT, GTS/BKN Broken Hill NSW, MTN Griffith NSW, GLV/BCV Regional VIC, MDV Mildura, TNQ Regional QLD, TDT Tasmania, GTS/BKN Spencer Gulf SA, SES/RTS Eastern SA, WDT Regional WA and Remote Central & Eastern.
When GO! was in development stages, the concept name was revealed as GO!99 on 14 April 2009 with a black and white concept logo. On 15 July 2009, news program A Current Affair confirmed the name as GO! along with a scheme of multi-coloured logos based on the original concept logo. On 2 February 2014, the channel's branding was refreshed with a new, 3D glossy logo with multi-coloured gradient variants. Following the network-wide rebrand on 26 November 2015, the channel was renamed 9Go! with the famous "nine dots" from Nine's logo integrated into then-current logo, but with the O in lowercase. WIN Television has a variant of the GO! logo with the aforementioned channel's logo above GO!'s 2009-2014 logo.9 August 2009 – 2 February 2014: Good to GO! (first era) (accompanied in promotional trailers by "Go!'" by Noise International feat. Sharon Muscat)
Christmas slogan (since 2009): GO! HO! HO!
2010 – 2012: Let's GO! (accompanied in promotional trailers by "Hello'" by The Potbelleez)
2 February 2014 – 26 November 2015: GO! For It!
26 November 2015 – present: Good to Go (second era)