Collings trained at Byam Shaw School of Art, and still practises as an artist, but until recently this was overshadowed in the public eye by his work as a commentator. He edited Artscribe 1983-7 with some success but was dismissed by the publisher after an argument. He was a producer and presenter on the BBC The Late Show 1989-95. In the early 1990s, he introduced BBC audiences to such contemporary avant-garde figures as Jeff Koons, Martin Kippenberger and Damien Hirst. He brought Kippenberger into the BBC studios to create an installation, and he interviewed Georg Herold, while the Cologne-based conceptual artist painted a large canvas with beluga caviar. Collings also wrote and presented documentary films for the BBC on individual artists, such as Donald Judd, Georgia O'Keeffe and Willem de Kooning, as well as broader historical subjects such as Hitler's "Degenerate Art" exhibition, art looted in the Second World War by Germany and Russia, Situationism, Spain's post-Franco art world and the rise of the Cologne art scene.

After leaving the BBC he wrote and presented the Channel 4 TV series This is Modern Art, which won him a Bafta (1998) among other awards. He was originally identified as a proponent of Britart, however more recently his sympathies have become ambiguous or even hostile to it. He wrote in the New Statesman:

"A new popular audience is obsessed by contemporary art. But I think they are being sold something that isn't really there: an all-in package of spirituality, depth and profundity. I am afraid the official institutions of contemporary art are just lying about this stuff."

Collings wrote and presented a Channel 4 series in 2003 about the "painterly" stream of Old Master painting, called Matt's Old Masters. A book by the same title accompanied the series. Further Channel 4 series by Collings included Impressionism: Revenge of the Nice (2004) and The Me Generations: Self Portraits, (2005).

In October 2007, with Emma Biggs Collings curated and wrote a catalogue essay for an exhibition of Picasso's late works at the HN Gallery in London. The paintings were from the 1960s series of Painter and Model and Déjeuner sur l’herbe reworkings. According to the catalogue essay the exhibition aimed to draw attention to Picasso's achievement as a manipulator of form rather than the popular myth of Picasso as a showman or lover or sensationalist genius.

That year, Collings presented the Channel 4 TV series "This is Civilisation". From 1997 to 2006, he presented Channel 4's annual live coverage of the Turner Prize award. His take on the event sometimes shocked or irritated some parts of the art establishment because of its flippancy and even contempt, though to others it was clear that it was not ignorance but knowledge that drove him, and he was more confident about the world he made light of than the people who attacked him.In 2009 he also appeared on the BBC2 programme "School of Saatchi" a reality TV show for newly trained UK artists. He lectures at City and Guilds of London Art School.

Collings' abstract paintings are created in collaboration with mosaicist, Emma Biggs.