Families and households in the UK: 2017

• In 2017 there were 19.0 million families in the UK, a 15% increase from 16.6 million in 1996.

• With 12.9 million families, the married or civil partner couple family remains the most common in 2017, with the cohabiting couple family growing the fastest.

• In the UK there were 27.2 million households in 2017, resulting in an average household size of 2.4.

• In 2017, there were 3.9 million people living alone aged 16 to 64 years; a larger proportion were male (58.5%); similarly there were 3.8 million people living alone aged 65 and over but a larger proportion (66.5%) were female.

• Young males were more likely to be living with their parents than young females; around 32% of males aged 20 to 34 years were living with their parents compared with 20% of females aged 20 to 34 years in 2017.

“In 2017, the most common family type in the UK was the married or civil partner couple family (12.9 million families). Opposite-sex couples were most likely to be in married couple families whereas same-sex couples were most likely to be in cohabiting couple families. This is likely to be because civil partnerships and marriages between same-sex couples in particular, are relatively new legal union statuses.”

Emily Knipe, Population Statistics Division, Office for National Statistics.

Follow Population Statistics Division on Twitter @RichPereira_ONS

A family is a married, civil partnered or cohabiting couple with or without children, or a lone parent, with at least one child, who live at the same address. Children may be dependent or non-dependent.

A household is one person living alone, or a group of people (not necessarily related) living at the same address who share cooking facilities and share a living room, sitting room or dining area. A household can consist of a single family, more than one family, or no families in the case of a group of unrelated people.

Dependent children are those aged under 16 years living with at least one parent, or aged 16 to 18 years in full-time education, excluding all children who have a spouse, partner or child living in the household.

The families and households estimates are based on social survey data from the April to June quarter of the Labour Force Survey (LFS) household dataset. This dataset is available from 1996 onwards.

Measures of quality (to show the levels of uncertainty associated with survey estimates) are presented in the datasets. You are advised to consult the quality measures when interpreting the estimates.

Families and households estimates for the reference years 2013 to 2016 have been revised following the re-weighting of the LFS. The estimates for these years will differ from previous publications.

In 2017 there were 19.0 million families in the UK; this increased by 15% from 16.6 million in 1996, a rise similar to the growth in the UK population during this 20-year period.

There were 12.9 million married or civil partner couple families in the UK in 2017. This remains the most common type of family. The second largest family type was the cohabiting couple family at 3.3 million families, followed by 2.8 million lone parent families.

The three main family types have all increased in number since 1996 (the first year Labour Force Survey (LFS) data are available). The fastest growing family type over the 20-year period was the cohabiting couple family, which more than doubled from 1.5 million families in 1996 to 3.3 million families in 2017 (Figure 1). This may be explained by an increasing trend to cohabit instead of marry, or to cohabit before marriage, particularly at younger ages.

There is currently no such thing as common law marriage in UK law, meaning cohabiting couples do not have the same legal rights as married couples. The Cohabitation Rights Bill, which addresses the rights of cohabiting couples, is in the early stages of passing through Parliament.

The number of lone parent families grew by 15.2%, a statistically significant increase¹; married couple families grew very little (1.5%), also a statistically significant increase, over the two decades. The number of lone parent families in the UK has been decreasing in recent years from 3.0 million in 2015 to 2.8 million in 2017, a statistically significant decrease. Cohabiting couple families have been more common than lone parent families in the UK in the last couple of years.

The most common family type for couples of the same sex was the same-sex cohabiting couple family, at 101,000; this was followed by civil partner couple families, at 55,000 and same-sex married couple families, at 34,000 (Table 1.)

Conversely, opposite-sex couples were most likely to be in a married couple family rather than a cohabiting couple family. These differences are likely to be associated with marriages between couples of the same sex being a relatively new legal union status, and the availability of civil partnerships, which provides an alternative to marriage for same-sex couples. Even considering marriages and civil partnerships together, couples of the same sex were most likely to be in cohabiting couple families in 2017.

The number of same-sex couple families in the UK has been increasing steadily since 1996; this could be associated with larger proportions of the population identifying as lesbian, gay or bisexual (LGB).

In 2017, families with no children or without dependent children were more common than families with dependent children. Despite this, there were 14.0 million dependent children living in families in the UK in 2017.

The types of families in which dependent children live have changed in line with the shift in family types since 1996. The percentage of dependent children living in cohabiting couple families (including both opposite- and same-sex couples) increased from 7% in 1996 to 15% by 2017. Dependent children living in a married couple family (including both opposite- and same-sex couples) fell by 9 percentage points to 64% in 2017. The percentage of dependent children living in lone parent families changed little over the two decades; 21% lived in lone parent families in 2017 compared with 20% in 1996.

In 2017, of all lone parents with dependent children, 55% had only one child, higher than both other family types (Figure 2). Further, only 13% of lone parents had three or more children. Conversely, married couples with dependent children had more children on average than other family types and only 40% had only one dependent child. These patterns are likely to reflect the stability of parental partnerships, as well as the fact that people often marry after having a child and then have further children within marriage; this is demonstrated in the registration status at birth statistics.

Notes for: Number of families in the UK continues to grow, with cohabiting couple families growing the fastest

1. If a change or a difference between estimates is described as “statistically significant”, it means that statistical tests have been carried out to reject the possibility that the change has occurred by chance. Therefore statistically significant changes are very likely to reflect real changes in families and household structures.

There were 27.2 million households in the UK in 2017. The number of households has increased by 6% since 2007, similar to the growth in the UK population during this period. As a result, average household size has remained at 2.4 people over the decade.

Table 2 shows that the most common household type in 2017 contained one family consisting of a couple with or without children. There were 15.7 million such households, an increase from 14.6 million in 2007 and 13.9 million in 1996. Despite this increase in absolute numbers, there has been little change in the proportion of all households of this type, remaining at 58% of all households in 2017, the same as 1996.

The next most common household type was one-person households, of which there were 7.7 million in 2017. UK households containing one lone parent family increased from 2.3 million in 1996 to 2.7 million in 2017.

Households containing two or more families (multi-family households) were the fastest growing household type over the decade to 2017, increasing by 42.1% from 215,000 households in 2007 to 306,000 households in 2017. This increase is statistically significant. Families in these households may be unrelated, or may be related in some way, for example, a married couple with their son and his girlfriend.

Changes in the number of multi-family households may be because of older couples moving in with their adult child and their family, young adults who are partnered or lone parents, remaining or returning to their parent’s household and unrelated families sharing a household. Despite this rise, which was also seen in the 2011 Census results, multi-family households still only represented a very small proportion (1.1%) of all households in 2017.

In 2017, around 28% of households contained one person (Figure 3). Although this has not changed much over the last decade, another source, the General Lifestyle Survey, which provides a longer time series, shows that 17% of households in Great Britain contained one person in 1971. Although not directly comparable, this suggests that the proportion of one-person households has increased considerably since the early 1970s.

Of the 7.7 million one-person households in the UK, 53.8% of them in 2017 contained one woman and 46.2% of them contained one man.

There were 3.9 million people living alone aged 16 to 64 years in 2017; a larger proportion were male (58.5%) than female. This could be because of the following:

• higher proportions of men than women never marry

• men marry at older ages than women and marry women younger than themselves

• partnership dissolution, leading to men living alone while women may live with any children from the relationship

Further studies by academics looking at living arrangements in mid-life are available.

For those aged 65 and over, the pattern is reversed; at these ages the larger proportion of people living alone were female (66.5%). This is partly because there are more women than men in the total population aged 65 and over due to women’s higher life expectancy. By the age of 65, most women have been married¹ and husbands are typically older than their wives. These two factors mean that more women than men become widowed, which may lead to living alone. In spite of this, the number of widowed women is falling due to life expectancy increasing faster for men compared with women.

Those living alone aged 45 to 64 years increased by 53% between 1996 and 2017, a statistically significant increase (Figure 4). This is partly due to the increasing population aged 45 to 64 years in the UK over this period, as the 1960s baby boom generation have been reaching this age group particularly in the last decade. The increase could also be due to a rise in the proportion of the population aged 45 to 64 years who are divorced or single never married.

Those aged 65 to 74 years living alone saw a statistically significant increase of 15% over the two decades. The number living alone aged 75 and over also increased over the two decades to 2017; this was by a larger percentage of 24%, which was also a statistically significant change. The reasons for increasing numbers of older people staying at home for longer are explored in our census analysis of the care home population.

In contrast, the number living alone in the 25 to 44 age group fell by 16% between 1996 and 2017; this was a statistically significant change. The number living alone in the 16 to 24 age group fluctuated over the two decades from 1996 to 2017. Lower numbers of young adults living alone is reflected in the increasing numbers of young adults who are living with their parents.

In 1996, around 5.8 million 15- to 34-year-olds in the UK lived with their parents; this increased to a peak of 6.7 million in 2014 (a statistically significant increase) and remained around 6.6 million in 2017 (Figure 5). Although the total population aged 15 to 34 years in the UK has increased over the time period, the percentage living with their parents has risen from 36% in 1996 to 40% in 2017.

A large percentage of 15- to 19-year-olds would be expected to be living with their parents; the number of young adults living with their parents decreases with age. Looking at 20- to 34-year-olds, the number living with their parents has increased from 2.7 million in 1996 to 3.3 million in 2013 (a statistically significant increase) and has since remained around 3.4 million. The percentage living with their parents has risen from 21% in 1996 to 26% in 2017.

Young males were more likely than young females to be living with their parents in 2017. Around 45% of males aged 15 to 34 years were living with their parents and 32% of males aged 20 to 34 years were living with their parents. This is compared with 34% of females aged 15 to 34 years and only 20% of females aged 20 to 34 years living with their parents.

Larger numbers of young adults tending to stay at home for longer may be explained by staying in education and training for longer, formalising relationships and having children at older ages, and increased costs in renting or buying a home. This is explored further in our Visual.ONS article Why are more young people living with their parents?

Notes for: How does the number of people who live alone vary by age and sex?

1. Statistics showing the proportion of men and women ever married by certain ages are also available.

For more detailed statistics, please see our datasets.

For further information on the Labour Force Survey, please see the user guide.

Further statistics on marriages (including marriages of same-sex couples), divorces and civil partnerships are available.

Population estimates by marital status and living arrangements provide the estimated population by age group, sex, marital status (single, married, civil partnered, divorced, and widowed) and living arrangements for England and Wales.

The General Lifestyle Survey provides statistics on households, families, marriages and cohabitation back to the 1970s.

The estimates presented within this bulletin and the associated datasets for the reference years 2013 to 2016 have been revised following re-weighting of the Labour Force Survey (LFS). The estimates for these years will differ from previous publications. A dataset assessing the impact of the re-weighting to the estimates for these years has been published alongside this release.

If a change or a difference between estimates is described as “statistically significant”, it means that statistical tests have been carried out to reject the possibility that the change has occurred by chance.

Therefore, statistically significant changes are very likely to reflect real changes in families and household structures.

A small number of children are excluded from the analysis on families. These include foster children and children who live in communal establishments that are not covered by the Labour Force Survey.

Since 2011, a household has been defined as one person living alone, or a group of people (not necessarily related) living at the same address who share cooking facilities and share a living room, sitting room or dining area. Previously a household was defined as a person living alone, or a group of people living at the same address who have the address as their only or main residence and either share one main meal a day or share living accommodation (or both). The aim of the change in definition was to ensure consistency with the definition used in the 2011 Census but has no impact on the comparability of the statistics over time.

The Families and Households Quality and Methodology Information report contains important information on:

• the strengths and limitations of the data and how it compares with related data

• uses and users of the data

• how the output was created

• the quality of the output: including the accuracy of the data

We publish family and household estimates for the UK only. Requests for additional data or data for alternative geographies can be made by emailing pop.info@ons.gov.uk or by calling +44 (0)1329 44 4661.

The revisions policy for population statistics is available.

Details of the policy governing the release of new data are available from the UK Statistics Authority website.