Armando Iannucci conceived the idea for a modern political satire after arguing the case for Yes Minister in a documentary made for a 2004 Best British Sitcom poll on BBC Two, realizing that while political issues remained relevant, the dynamics had shifted toward pressure from Downing Street rather than Civil Service resistance.

Iannucci was struck during his research by how much responsibility was placed in the hands of young special advisers, noting that cabinet ministers hired confident but inexperienced graduates who had never done anything as mundane as fixing a car or buying a house.

The show was commissioned by BBC Four controller Roly Keating with a very limited budget of £100,000; Iannucci later said this small budget was actually a positive, forcing an experimental approach to producing the series.

Journalist and former civil servant Martin Sixsmith served as an adviser to the writing team, helping add realism to some scenes.

The first series was filmed in a former Guinness brewery in Park Royal, west London, and was shot with hand-held cameras and wireless microphones to create a fly-on-the-wall documentary feel, with no incidental music or laughter track.

One of the key stylistic reference points for the direction was the Dogme 95 film movement, particularly the film The Celebration; actors were free to move around the set as they wished during takes, with camera operators following them.

Peter Capaldi noted that although around 80% of the final cut came from the original script, cast members improvised additional dialogue, credited as 'additional material', to make scenes feel more real.

Before rehearsals, scripts were sent to Ian Martin, credited as a 'swearing consultant', who added some of the show's more colorful profanity.

Chris Langham did not return for the 2007 Christmas specials as Hugh Abbot due to his arrest and later conviction on charges of possession of child pornography, prompting Iannucci to introduce new opposition characters to fill the gap.

The character Malcolm Tucker is patterned partly on real-life government director of communications Alastair Campbell, as well as on Hollywood producers such as Harvey Weinstein.

The term 'omnishambles', coined on the show in 2009, later entered real British political discourse after being used to describe George Osborne's 2012 budget, and by 2013 had entered the Oxford English Dictionary.

Sony Pictures produced an American remake pilot for ABC in 2007, directed by Christopher Guest, but Iannucci distanced himself from it, calling it 'terrible' because it was conventionally shot with no improvisation or swearing; the show was not picked up.

Following the failed American remake, Iannucci was invited by HBO to create Veep, a series with a similar tone and political themes, involving some of the same writers and production members from The Thick of It.

In The Loop, the feature film spin-off, was nominated for an Academy Award for Best Adapted Screenplay in 2010.

The Thick of It was ranked the fourth-greatest show of the 21st century by The Guardian in 2019, and placed at No. 20 in a BBC Culture poll of 206 critics and industry figures for the 100 greatest television series of the 21st century.