Millennial population of the UK 2023, by age and gender

There were approximately 14.69 million millennials in the United Kingdom in 2023. This generation, sometimes called Generation Y were born between 1981 and 1996 and are mainly the children of the post-war Baby Boomer generation. As of 2023, Millennials were the largest generational cohort in the UK, followed by Generation X at 14.04 million people, Baby Boomers at 13.57 million, and then by Generation Z at 13.2 million. The most numerous single-year of age for Millennials, and the UK as a whole, was 35 at 956,116.

Boomerang generation

The first cohort of millennials came of age at the turn of the century and have almost certainly been heavily influenced by the growth of internet accessibility during this time. The economic challenges faced by this generation may have a relation to the increasing share of young adults who live with their parents in the UK. This has led to the perhaps unfair, characterization of millennials as the boomerang generation, who failed to grow-up and mature. Some of these negative stereotypes regarding Millennials have since shifted to the next youngest generation, Generation Z, who have started to enter the workplace since the mid-2010s. 

Generation Remain

One of the main challenges that British millennials currently face are their prospects after Brexit. Although the United Kingdom voted to leave the European Union in June 2016, there were clear divisions between regions, classes and age-groups. Most millennials voted to remain in the Brexit referendum with 73 percent of people aged 18 to 24, and 62 percent of those aged 25 to 34 voting to remain. In the next UK election, the majority of 25 to 49-year-olds intend to vote for the Labour Party, with only a slight majority of those over 65 planning to vote for the Conservative Party. Millennials also still appear to oppose Brexit, with approximately 65 percent of 25 to 49-year-olds believing Brexit to have been the wrong decision.