The first match on ITV will be Real Madrid at Levante on Sunday, while digital platform Eleven Sports will continue to show nine games per week while losing its exclusivity deal on broadcasting Spanish football.
The announcement came a day after pay TV platform Premier Sports said it would be showing four La Liga games per week for the rest of the season.
ITV will have second pick of the week's fixtures from Spain's top flight, but will not broadcast the 'Clasico' between Real Madrid and Barcelona on March 2.
"We are delighted to welcome Premier Sports and ITV Sport to our broadcaster stable in the UK and Ireland which already includes Eleven Sports," La Liga President Javier Tebas said in a statement.
"This is a fantastic moment for La Liga in the UK and Ireland. The best league in the world will be available to more fans than ever before."
The deal will make La Liga available to Britain's 27 million television homes, the league added, significantly increasing its visibility in Britain, which took a hit when Sky Sports ended its 20-year-long coverage of the league in 2018.
Eleven Sports, a digital only platform belonging to Leeds United owner Andrea Radrizzani which aimed to be the Netflix of sports broadcasting, has struggled to make in-roads in the British market and this month said it would no longer show Serie A, forcing it to drop its monthly subscription price.
The move could also see Spanish football rival the Premier League, which is only available in Britain on pay TV platforms Sky Sports and BT Sport, for viewing figures.
“Few countries have an appetite for football like the UK and Ireland and we are happy to provide multiple forms of access to the best league in the world, including La Liga’s first agreement to show free-to-air matches in the United Kingdom," added the league's audiovisual director Melcior Soler.
"This is part of our continued commitment to our fans to make La Liga available in as many ways as possible."
(Reporting by Richard Martin, editing by Ed Osmond)
