According to the first 2021 census results, the population of England and Wales has increased to 59,597.300.
It has grown by over 3.5 million (6.3%) in the last census in 2011 and now has more people older than ever.
Addition of published Northern Ireland census figures and an official estimate for the Scottish population for 2020 brings the UK's population to 66,966,400.
This is the largest increase since 1801 when the census was started.
It also shows that the population grew in all English regions and Wales.
Every ten years, the Office for National Statistics (ONS) conducts a census. It asks people questions about their homes, household, and themselves to create a comprehensive snapshot of society.
These results will help organisations plan and fund public services like transport and education.
The survey 2021 was conducted on 21 March 2018, against the backdrop Brexit, which has seen restrictions placed on immigration, and the coronavirus epidemic.
This census has the greatest impact on the local detail.
Each local authority's population determines how much funding they receive. If Tuesday's figure is significantly lower than the projected population for the area, budget cuts could be possible.
On census day, the number of people living in Kensington and Chelsea was 10% less than in the 2011 census.
Westminster fell 7%. One theory suggests that some of those in wealth had moved to second or third homes during this pandemic.
Tewkesbury was the place with the greatest increases, followed by Vale of White Horse at the Cotswolds edge.
These figures show that one-sixth (18.6%, 11. million) of 2021's population are over 65. This is an increase from 16.4% (9.2million) in 2011.
About 0.9% of the population (527,000 people) are over 90 years old. This was 0.8% of the population in 2011, or 429,017.
The figures show that there were 10.4 millions people 15-years-old and younger in 2021. This represents 17.4% of the total population.
This age group has more people than in 2011, but the percentage of the population under 15 years old has fallen slightly, from 17.6% in 2011.
The east of England saw the greatest population growth, with 488,000 new residents since 2011, an 8.3% increase.
The smallest growth in population was recorded in Wales, at 1.4%. Meanwhile, the north-east England saw an increase of 1.9%.
Sunderland and Swansea are just a few of the large cities and towns that have seen their population decline.
Tower Hamlets in east London, which saw 22.1% population growth, was the place with the greatest increases.
All three cities saw significant increases in Bedford, Cambridge, and Peterborough.
The Census reflected the total population of 30,420,100 females (51.0%) and 29,177 200 men (49.0%), respectively in England and Wales.
The last decade has seen a slight slowdown in population growth. The population growth in England and Wales between 2001 and 2011 was 7.8%.
Half a million more people were counted than expected in the census.
The ONS announced that data from the 2021 census in England and Wales will be released in stages over the course of the next two-years.
Future releases will include data on ethnicity, religion and the labour market as well as education and housing.
For the first time, information will also be available on veterans of the UK Armed Forces, as well as sexual orientation and gender identity.