ITV2 is a British free-to-air television channel owned by ITV plc. It was launched on 7 December 1998. For a number of years, it had the largest audience share after the five analogue terrestrial stations, a claim now held by its sister service ITV3 both of which are freely available to a majority of households.

The channel is primarily aimed at the 16–34 age group, similar to BBC Three and E4, and is known for American programming such as adult animations Family Guy, American Dad! and Bob's Burgers; repeats of recently aired episodes of soap operas and other entertainment programming from ITV such as Coronation Street, Emmerdale and Catchphrase; original comedy such as Celebrity Juice and Plebs; and reality formats such as Big Brother and Love Island.

Prior to the launch of Channel 4 in 1982, the name "ITV2" had sometimes been used to refer informally to an envisioned second commercial network in the UK. However, the name resurfaced in the late 1990s for very different reasons. The launch of digital terrestrial television services in the UK saw each existing analogue terrestrial broadcaster given a slice of bandwidth with which to carry their existing service after the analogue switch off, with space left over for new channels. While strictly speaking this space belonged to each regional contractor for use within their own region, ITV had undergone a series of buyouts earlier in the decade; the three players operating the majority of the network, Granada, Carlton, and United News & Media, jointly launched ITV2 in 1998 to be broadcast to most of the country as a uniform service. While free-to-air, it was marketed alongside their own subscription based ONdigital platform. Other ITV licencees, SMG, UTV and GMTV launched their own services in the space (see below).

ITV2 was announced in May 1998, and the channel's original controller was Brian Barwick.

ITV2 launched at 7:00 pm on 7 December 1998. The first programme was an hour-long introductory programme called It Takes Two, presented by Gabby Logan and Vinnie Jones. Billie Piper was heavily involved in the channel's promotion at launch, with an updated version of the 1966 song It Takes Two sung by her used as the theme song for the launch programme and featured in the original promos for the channel.

While ITV2 is now an entertainment channel aimed to a younger audience; at its launch in 1998, it was a mixed genre channel and featured some programmes aimed at much older audiences than what the channel broadcasts currently. Despite this, the channel was launched to target a younger, more male audience.

Much of the original content in its launch schedule was current affairs related programming fronted by ITV newscasters. Katie Derham presented a weekly media analysis programme called Wide Angle, John Suchet fronted a weekly current affairs discussion programme called Who, What, Why, and Trevor McDonald presented an interview series, Trevor McDonald Meets.... These three programmes all ran on Sunday nights.

There were repeats of popular ITV programmes including Midsomer Murders, Inspector Morse, A Touch of Frost, Heartbeat, Who Wants to Be a Millionaire?, Gladiators, CD:UK, Don't Try This at Home, Trisha, This Morning, Loose Women and My Wonderful Life, American acquisitions such as Judge Judy, The Jerry Springer Show, The Late Show with David Letterman and Maggie Winters, omnibus editions of ITV soaps Emmerdale, Coronation Street, The Bill and Home and Away, and a Saturday football results service called Football First, which was promoted to ITV1 in 2001 (while maintaining an ITV2 slot) and rebranded as The Goal Rush. Other launch programmes included youth magazine show Bedrock and Soap Fever which taken a look at the UK's major television soap operas. There was also live coverage of the UEFA Champions League among a range of other sports coverage. Many of the older-skewing drama series were dropped after the launch of ITV3 in 2004, and the launch of ITV4 the year later saw ITV2 ditch sports coverage, except on certain occasions as overspill.