Families and households in the UK: 2018

• In 2018, there were 19.1 million families in the UK, an increase of 8% from 17.7 million in 2008.

• The number of cohabiting couple families continues to grow faster than married couple and lone parent families, with an increase of 25.8% over the decade 2008 to 2018.

• The number of same-sex couple families has grown by more than 50% since 2015, with more than four times as many same-sex married couple families in 2018 compared with 2015.

• In 2018, there were 27.6 million households, an increase of 350,000 on the previous year and 1.7 million since 2008.

• The number of people living alone in 2018 has surpassed 8 million, up from 7.7 million in the previous year, driven by increases in women aged 45 to 64 years and men aged 65 to 74 years.

• In 2018, one in four young adults (3.4 million) aged 20 to 34 years were living with their parents.

“The number of families and households in the UK has continued to rise in line with the growth of the UK population over the past decade. However, the ways that people live have been changing.

“While married couple families remain the most common, cohabiting couples are the fastest growing family type as people increasingly choose to live together before, or without, getting married.

“There are also more people living alone than ever before, an increasing number of same-sex couple families and more young adults living with their parents.”

Sophie Sanders, Population Statistics Division, Office for National Statistics

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.

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.

Non-dependent children are those living with their parent(s), and either (a) aged 19 years or over, or (b) aged 16 to 18 years who are not in full-time education or who have a spouse, partner or child living in the household. Non-dependent children are sometimes called adult children.

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.

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 2012 to 2017 have been revised following the re-weighting of the Labour Force Survey (LFS). The estimates for these years will differ from previous publications.

Families and household statistics explained provides further information on the complexities around the definitions and how these relate to situations people might be experiencing.

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.

In 2018, the number of families in the UK continued to rise to 19.1 million. This is a statistically significant increase of 7.6% from 17.7 million in 2008. The rise over the last 10 years is in line with the growth in the UK population over this period of 7.5%.

Married and civil partner couple families were the most common family type in the UK in 2018, representing two-thirds (67.1%) of all families. Cohabiting couple families were the second-largest family type at 3.4 million (17.9%), followed by 2.9 million (15%) lone parent families. Since 2008, the share of married couple families has declined from 69.1% of all families, while the share of cohabiting couple families has increased from 15.3%.

Cohabiting couple families were the fastest-growing family type over the last decade with a statistically significant increase of 25.8% from 2.7 million in 2008 (Figure 1). This may be explained by an increasing trend to cohabit instead of marrying, or to cohabit before marriage.

There is no such thing as a common law marriage in the UK, meaning that 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.

There have been no significant changes to the number of lone parent families between 2008 and 2018.

Same-sex couple families

The numbers of same-sex couple families have increased substantially in recent years, with an increase of 53.2% from 152,000 in 2015¹ to 232,000 in 2018.

Same-sex cohabiting couple families remain the most common same-sex couple family, but the proportion of these has declined from 59.6% in 2015 to 50.4% in 2018. Civil partner couple families have also decreased from 31.5% to 20.2% of all same-sex couple families.

The introduction of same-sex marriages in March 2014² has led to rapid growth in same-sex marriage couple families. Since 2017, the number of same-sex marriage couple families has doubled to 68,000 (a statistically significant increase) representing 29.4% of all same-sex couple families in 2018 compared with only 8.9% in 2015 (Figure 2).

This contrasts to opposite-sex couple families in which 79.4% are married couple families and 20.6% are cohabiting couple families. The trends for opposite-sex and same-sex couple families are going in opposite directions, with the share of opposite-sex married couple families decreasing, while opposite-sex cohabiting couple families are increasing (although at a much slower rate of change than for same-sex couple families).

The Civil Partnerships, Marriages and Deaths (Registrations Etc.) Act, which received Royal Assent on 29 March 2019, contains provisions for regulations to be made to extend eligibility for forming a civil partnership to opposite-sex couples in England and Wales. This is expected to come into effect by 31 December 2019.

Families with children

Married or civil partnership couple families and cohabiting couple families can include dependent children, non-dependent children or no children. Lone parent families include either dependent or non-dependent children. In 2018, almost two in five couple families had dependent children living with them at their address, while 1 in 10 had only non-dependent children living with them. Half of all couple families had no children living with them.

Families with dependent children (both couple and lone parent families) have had a statistically significant increase of 5.6% from 7.6 million in 2008 to 8 million in 2018, while families with non-dependent children have also had a statistically significant increase of 16.4% to 2.9 million. The rapid increase in families with non-dependent children is reflected in the numbers of young adults living with their parents (see Section 6).

Married or civil partner couple families remain the most common type of family in which dependent children live (63.5%), followed by 21.1% in lone parent families and 15.3% in cohabiting couple families. Cohabiting couple families have had the largest statistically significant percentage increase of those families with dependent children at 23.9% in the decade 2008 to 2018, rising to 1.3 million in 2018.

In 2018, of all families with dependent children, lone parent families had fewer children on average than cohabiting or married couple families. Among lone parent families, 54.5% had one child, which was a higher proportion than both other family types, 32.1% of lone parents had two children and 13.3% of lone parents had three or more children.

Conversely, married couples with dependent children had more children on average than other family types (Figure 3). These patterns could reflect the perceived stability of parental partnerships, as well as that people often marry after having a child and then have further children within marriage; this is demonstrated in the birth characteristics statistics.

Notes for: Number of families continues to grow, with large increases for same-sex couple families

1. Although same-sex marriage in England and Wales has been legal since 13 March 2014, none appear in the Labour Force Survey data until 2015 so this is the earliest year we can compare to.

2. Legislation to allow same-sex marriage in England and Wales came into effect on 13 March 2014, while for Scotland the legislation came into effect on 16 December 2014. Legislation requiring the UK government to extend same-sex marriage to Northern Ireland (if the Northern Ireland Assembly is not resumed before 21 October 2019) has passed Parliament and will come into effect on 13 January 2020.

In 2018, there were 27.6 million households in the UK, a statistically significant increase of 1.3% since 2017 and 6.6% in the 10-year period from 2008.

Since 2017, an additional 292,000 people (a statistically significant increase of 3.8%) aged 16 years and over are estimated to live alone bringing the total number of one-person households to just over 8 million (15% of the UK adult population) in 2018.

This has been driven by statistically significant increases in 45- to 64-year old women and 65- to 74-year old men living alone (Figure 4). Reasons for increases in these age and sex groups include:

• increasing population aged 45 to 64 years

• rises in the proportions who are divorced or single never married

• increasing male life expectancy catching up with female life expectancy

See our article Living alone: one-person households for more information on the characteristics of those people living alone.

There were 4.1 million people under the age of 65 years living alone in 2018, a statistically significant increase of 5.1% since 2017, but longer trends from 2008 show no significant change. Comparatively, those aged 65 years and over living alone have increased by half a million people to 3.9 million between 2008 and 2018, a statistically significant increase of 14.8%.

There continues to be more men living alone under the age of 65 years than over and more women living alone over the age of 65 years than under. This could be because of the following:

• higher proportions of men than women never marry

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

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

• women’s higher life expectancy

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

Although more women than men live alone at the oldest age groups, men are experiencing the fastest increases with statistically significant increases of 55.6% for 65- to 74-year old men between 2008 and 2018 and 20.1% for those aged 75 years and over (Figure 5).

Women aged 75 years and over occupy the largest proportion of those living alone, but there has been no significant change for this group since 2008. This could partly be explained by life expectancy increasing faster for men compared with women closing the gap between women and men.

There have been statistically significant declines observed in the younger age groups for men aged 16 to 24 and 25 to 44 years and women aged 25 to 44 years. This is likely caused by the increasing numbers of young adults who live with their parents (see Section 6).

Other household types

Whilst the number of households has grown over time, the proportional split of household types has remained consistent over the past two decades, 1998 to 2018.

In 2018, one-person households represented 29% of all households, but the most common household type was one-family households representing two-thirds of all households (66.8%). The remaining household types, households with two or more unrelated adults and multi-family households, represented a much smaller share of total households at 3% and 1.1% respectively.

One-family households have increased by 6.9% since 2008, reaching 18.4 million in 2018.

Lower numbers of young adults are living alone (Section 5) and there is an increasing number of young adults living with their parents. In 2018, one in four young adults aged 20 to 34 years were estimated to live with their parents. This is a statistically significant increase of 24% over the 10-year period 2008 to 2018. However, the increases seen in the number of young adults living with their parents since 2013 are much more gradual than the increases in previous years (Figure 6).

Over the past two decades, young men have always been more likely than young women to live with their parents. In 2018, 31.4% of men aged 20 to 34 years and 19.9% of women aged 20 to 34 years were living with their parents. This is likely because women tend to marry at younger ages than men and it is possible that women are also more likely to cohabit at younger ages than men.

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 article Why are more young people living with their parents?

For more detailed statistics, please see our families and households 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 2012 to 2017 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.

The Families and households Quality and Methodology Information report contains important information to help you:

• understand the strengths and limitations of the data

• learn about existing uses and users of the data

• reduce the risk of misusing data

• to decide suitable uses for the data

• understand the methods used to create 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. Please note requests for additional data are likely to be charged in line with our charging policy (PDF, 65KB).

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.