The US internet-delivered streaming service is available on a range of devices including all three major games consoles, the iPad and iPhone, Android tablets and phones, LG Blu-ray players and Samsung Smart TVs.
Netflix, which has an estimated 20 million members in 47 countries, announced it would be entering the European market in November last year, after a failed attempt seven years ago.
It faces tough competition in the subscription video-on-demand market in the UK, from the likes of Amazon’s LoveFilm, Sky and Virgin Media.
LoveFilm, which has an established brand in the UK and unlike Netflix offers DVD rental in the UK, recently launched a £4.99 per month online-only package as a short term offer. It has been bolstering its streaming service by accelerating its content partnerships in recent months.
Since revealing its launch plans Netflix has been racking up content deals and launches with films and TV content from partners including Lionsgate, Channel 4, BBC Worldwide, ITV, 20th Century Fox, Sony Pictures Entertainment, MGM, Miramax Momentum Partners and Disney UK and Ireland.
This means movies such as 'The Aviator' and 'Man on Wire' and TV programmes including 'The Inbetweeners' and 'The Only Way is Essex' will be available to stream today.
It has also partnered with Facebook to launch a social app, similar to one it has in the US, which enables users to connect their Netflix account to the social network, to share what they are watching in their Timeline.
Reed Hastings, co-founder and chief executive officer of Netflix, who is in the UK today to announce the launch, said. "We are starting 2012 in the best possible way by giving consumers in the UK and Ireland an amazing entertainment experience."
Netflix’s announcement of the UK launch came after it was reported to have lost 800,000 subscribers in the US due to plans to increase prices and a high-profile u-turn on separating its DVD rental and streaming business.
In November its share price plunged after speculation that the launch would push it into the red.
However just last week the share price climbed after Netflix revealed its 20 million subscribers watched more than two billion hours of TV shows and movies on devices with high-speed Internet connections during the final three months of last year.