In addition to having one of the largest carnivals in Europe, the borough is also home to an array of the world's most expensive residential properties and Kensington Palace, which is the home of the British royal family.
The local authority is Kensington and Chelsea London Borough Council. Its motto, adapted from the opening words of Psalm 133, is Quam bonum in unum habitare, which translates roughly as 'How good it is to dwell in unity'.
Under the London Government Act 1963, when 86 boroughs and urban districts were reorganised into 32 London boroughs on 1 April 1965, along with the formation of Greater London Council, the borough was formed by the merger of the Royal Borough of Kensington and the Metropolitan Borough of Chelsea.
It had originally been intended to be known only as "Kensington", but after thousands of Chelsea residents protested, Sir Keith Joseph, then Minister of Housing and Local Government, announced on 2 January 1964 that the new borough would be known as the Royal Borough of Kensington and Chelsea.
As the home of Kensington Palace, where Queen Victoria was born in 1819 and lived until her accession in 1837, Kensington was granted the royal borough status in 1901. In 1689, Christopher Wren enlarged and rebuilt the original house for King William III, transforming it into a royal residence. As he ruled, Kensington Square became a popular residential area. The King brought many court officials, servants, and followers with him. Since 1760, the palace has been used regularly by monarchs and members of the Royal family.
Kensington and Chelsea are perhaps best known today for two events that demonstrate both their traditional and modern sides. Royalty and society's elite attend the Chelsea Flower Show every May in the grounds of the Royal Hospital; the Notting Hill Carnival, held every August Bank Holiday in North Kensington, has grown from a small community-based event over the past 30 years into Europe's biggest and most exuberant street party, attracting over a million visitors a year.
A 2011 census revealed that 158,649 people lived in the borough, 71% white, 10% Asian, 5% from multiple ethnicities, 4% from Black Africa and 3% from Black Caribbean. There are 32 London boroughs, but it is the least populated.
As of 2005, the borough occupied 19% of its land with domestic buildings, over half the national average, and 12% with non-domestic buildings, fifth highest in the country.
Based on statistics released by the Office for National Statistics in 2010, the life expectancy at birth of females in 2008–2010 was 89.8 years, the highest in the United Kingdom. The figures for males in 1991–1993 were significantly lower: 73.0 years for males (ranked 301st in the nation) and 80.0 years for females (ranked 129th).
It has been found that there is a 12-year gap between Chelsea's affluent wards (Royal Hospital, Hans Town) and North Kensington's most poor and socially disadvantaged wards (Golborne, Dalgarno).
Over 16.6% of the residents of the borough earn more than £60,000 per year, making it the borough with the highest proportion of financial sector workers and the lowest proportion of retail workers in the country.
Sport England published a survey in December 2006 indicating that the borough has the fourth highest rate of sports and fitness participation in England with 27.9% participating at least three times a week for 30 minutes each time.
As a result of a 2017 study by Trust for London and New Policy Institute, Kensington & Chelsea has the highest income inequality among London Boroughs. The borough's poverty rate, 28%, is roughly in line with the London-wide average. Private rent for low earners is also the lowest in London.