How many unmarried couples live together in the UK?

How many couples live together without marrying?

About 3.5 million families in the UK are headed by an unmarried couple who live together, which is roughly one family in six. The Office for National Statistics (ONS) reported in Families and households in the UK: 2025, released on 17 April 2026, that there were 19.9 million families in total, of which 13.0 million (65.3%) were married couples, 3.5 million (17.6%) cohabiting couples, about 216,000 (1.1%) civil partner couples and 3.2 million (16.0%) lone-parent families ^[1]. The previous edition, for 2024, gave almost the same picture: 3.5 million cohabiting couple families, or 17.7% of 19.7 million families ^[2].

Statisticians use the word family in a narrow sense. In the ONS definition, a family is a married, civil-partnered or cohabiting couple, with or without children, or a lone parent with at least one child, living at the same address ^[1]. The count therefore leaves out couples who live apart, and it excludes families in communal establishments such as care homes ^[2]. It is a snapshot of households, not a count of everyone who has ever cohabited.

The estimates come from the Labour Force Survey, a sample survey, and the ONS warns that falling response rates have made them less precise ^[2]. For 2025 it notes that the rise in the cohabiting share from 17.0% in 2015 to 17.6% in 2025 is not statistically significant ^[1]. In other words, the share has been broadly stable for a decade, even though the absolute number has crept up as the population has grown. The longer climb, from the 1990s to the 2010s, was much steeper, as the next section shows.

Married and cohabiting couples in the UK, and in England and Wales

Measure and year	Cohabiting couples	Married couples
UK families, 2014 (ONS)	3.1 million, 16.4% of families [2]	67.1% of families [2]
UK families, 2024 (ONS)	3.5 million, 17.7% of families [2]	12.8 million, 65.1% of families [2]
UK families, 2025 (ONS, released 17 April 2026)	3.5 million, 17.6% of families [1]	13.0 million, 65.3% of families [1]
England and Wales, couples living together, 1996	About 1.5 million [4]	Not given in the briefing [4]
England and Wales, couples living together, 2021	About 3.6 million, 22% of couples [4]	The remaining couples (married or in a civil partnership) [4]
England and Wales, people in a couple, census 2021	24.3% (20.6% in 2011) [5]	75.7% (79.4% in 2011) [5]

How has cohabitation grown since the 1990s?

Cohabitation has more than doubled in England and Wales since the mid-1990s. The House of Commons Library puts the number of cohabiting couples at around 1.5 million in 1996 and around 3.6 million in 2021, an increase of 144%, which made cohabitants 22% of all couples living together by 2021 ^[4]. The briefing is a guide to the legal position of unmarried couples, and it notes that many people are unaware how little legal status cohabitation gives them ^[4].

The census gives a second view, counting individuals rather than families. In England and Wales, 24.3% of people in a couple were cohabiting in 2021, up from 20.6% in 2011, while 75.7% were married or in a civil partnership, down from 79.4% ^[5]. The ONS published that analysis on 9 February 2023. The difference between the 22% and 24.3% figures comes from the unit being counted, since one counts couples and the other counts the people in them.

Within the 2010s the UK-wide family series moved more gently. In 2014 cohabiting couples made up 16.4% of families (3.1 million), and by 2024 they were 17.7% (3.5 million) ^[2]. An earlier bulletin recorded that opposite-sex cohabiting couple families were 17% of all families in 2023, up from 15% in 2013, and that they accounted for 469,000 additional families, or 42% of all growth in the number of families over the decade ^[3]. The ONS attributed much of that increase to couples without children at home, a group that includes couples who may have children later and couples whose children live elsewhere ^[3].

Research from the University of Southampton adds a generational angle. Its 2020 policy briefing found that 77% of partnerships now begin as cohabitations, and that couples typically start living together in their early twenties ^[8]. The authors describe cohabitation as increasingly a way of testing a relationship rather than a short step before a wedding, a theme taken up on the page about living together before marriage.

Who cohabits, and at what age?

Cohabitation is most common among adults in their late twenties and thirties, and the biggest rise has been among people in their late twenties. According to the 2021 census, the share of 25 to 29-year-olds in a couple who were cohabiting jumped from 56.5% in 2011 to 71.6% in 2021 ^[5]. Cohabitation rose in every age group below 85, which means it is no longer only a younger-generation habit ^[5].

Age gaps are narrowing. Among cohabiting couples in England and Wales, the share in which partners were five or more years apart fell from 38.5% in 2011 to 33.7% in 2021, while for married couples the share barely moved (31.0% in 2011, 31.1% in 2021) ^[5]. Cohabiting couples were once more likely than married couples to have a large age gap, and by 2021 the two groups looked more alike.

Same-sex couples are a small but growing part of the picture. In 2025 same-sex couples were 4.9% of cohabiting couples and 0.9% of married couples; ten years earlier, they had been 2.8% of cohabiting couples ^[1]. For 2024, the ONS reported 4.2% against 2.7% in 2014 ^[2]. Same-sex cohabiting couple families were 0.7% of all families, or 137,000, in 2023 ^[3].

Children complicate the pattern. The ONS bulletins do not break down cohabiting couples by whether they have dependent children, but they show that 42.8% of all UK families in 2025 had at least one dependent child ^[1]. The related question of how many babies are born to unmarried parents is covered in births outside marriage in the UK.

Is cohabitation replacing marriage?

Not entirely: marriage is still the most common form of couple family, but its share has slipped. Married couples were 67.1% of UK families in 2014, 65.1% in 2024 and 65.3% in 2025 ^[1][2]. The ONS describes the fall as part of a long-term trend of fewer couples marrying, alongside more couples living together without marrying ^[2]. The 2024 and 2025 figures suggest the slide has slowed.

The numbers of weddings point the same way. Opposite-sex marriage rates in England and Wales fell from 20.3 per 1,000 unmarried men in 2022 to 18.1 in 2023, and from 18.3 to 16.4 per 1,000 unmarried women ^[10]. Part of the fall is timing, because people are marrying later, a trend described in the average age at first marriage.

Cohabitation sometimes leads to marriage and sometimes does not. The Southampton briefing followed first cohabiting unions across three decades. Among unions formed in the 1980s, 53% had turned into marriages within five years and 19% had ended in separation. For unions formed in the 2000s, 36% had become marriages within five years and 35% had broken up ^[8]. After ten years, 61% of 1980s unions had become marriages, against 44% for 2000s unions, and separation rates were 25% and 42% respectively ^[8].

Only a minority remain unmarried and together for the long term: the briefing found that around 13% to 14% of first cohabiting unions were still going as cohabitations at ten years ^[8]. The authors conclude that the decline in marriage among cohabiters owes more to couples splitting up than to couples choosing to stay unmarried for good ^[8]. Civil partnerships complicate the picture a little, since civil-partner couples rose from about 61,000 families in 2014 to about 200,000 in 2024 ^[2].

How do the figures differ across the UK?

The four nations share the same direction of travel, but the measures differ, so comparisons need care. The ONS family series covers the UK as a whole, and the bulletin does not give separate national figures. It also notes that Labour Force Survey estimates for Northern Ireland are no longer published ^[1]. Census results fill the gap, each with its own definitions.

In Scotland, the 2022 census counted 1,251,600 households containing couples, up 4.5% since 2011. Households with cohabiting couples grew by 25.2% between 2011 and 2022 and by 80.8% since 2001, while the share of couple households that were married or in a civil partnership fell from 86.0% in 2001 to 76.6% in 2022 ^[6]. That puts roughly one couple household in four in Scotland on a non-marital footing.

In Northern Ireland, the 2021 census recorded 690,500 married adults, or 45.6% of everyone aged 16 and over, and 2,700 people in civil partnerships. Among about 794,400 people living in a couple, 115,700 were in opposite-sex cohabiting relationships and 5,700 in same-sex cohabiting ones ^[7]. Those figures put the cohabiting share of people in couples at roughly 15%, a calculation made here from the census counts, and noticeably lower than the 24.3% found in England and Wales ^[5][7]. NISRA adds a caution that the civil partnership count was higher than expected and was partly corrected using other relationship data ^[7].

Different units (families, households, couples, people) explain why the percentages differ from one source to another, and they should not be mistaken for conflicting findings. A reader who wants a trend should compare like with like, for example the 2011 and 2021 census shares for England and Wales, or successive editions of the same ONS bulletin.

Why do the numbers matter for law and policy?

The statistics matter because the law treats cohabiting and married couples very differently, especially in England and Wales. The Commons Library states plainly that cohabitation gives a couple no general legal status, whatever its length, while in Scotland cohabitants can make limited claims when a relationship ends or a partner dies ^[4]. The page on the common law marriage myth sets out those differences in detail.

Reform has been debated for almost two decades, and the figures are the usual starting point. The Ministry of Justice opened a consultation on 5 June 2026, titled A fairer end to relationships, covering financial remedies on divorce, financial provision for cohabitants on separation and inheritance for cohabitants on death, in England and Wales only ^[9]. It closed on 14 August 2026, and no government response or government bill had been found by 30 October 2026. A private member's bill, the Cohabitation Rights Bill [HL], sponsored by Lord Marks, was introduced in the Lords in the 2026-27 session ^[11]. Its progress is described on the page about cohabitation law reform in England.

In Scotland, cohabitants can make limited claims when a relationship ends or a partner dies, under the Family Law (Scotland) Act 2006 ^[4]. Northern Ireland has its own regime, with fewer rights for cohabitants than for married or civil-partner couples ^[4]. Whatever changes are made, any new rules would apply to a large group, since well over three million UK families are headed by unmarried partners ^[1].

Frequently asked questions

Is cohabitation the fastest-growing family type in the UK?

Not in recent years. Cohabiting couple families rose from about 3.1 million in 2014 to 3.5 million in 2024, roughly 13% in number, while all families grew by 5.7% ^[2]. Civil-partner couples grew faster in proportion, from about 61,000 to 200,000, but from a very small base ^[2]. The ONS says the rise in the cohabiting share between 2015 and 2025 is not statistically significant ^[1].

How long do cohabiting couples usually stay together?

There is no single average, because many cohabiting unions end in marriage or separation. Southampton research found that only 13% to 14% of first cohabiting unions were still cohabitations after ten years ^[8]. The rest had become marriages or ended in separation. The ONS bulletins do not report the length of cohabitation.

Do most cohabiting couples eventually marry?

Fewer do than in the past. Of first cohabiting unions formed in the 1980s, 61% had become marriages within ten years, but the figure was 44% for unions formed in the 2000s ^[8]. Over the same period the share ending in separation within ten years rose from 25% to 42% ^[8].

Where do the ONS figures come from?

The family and household figures come from the Labour Force Survey, a sample survey of households, so they are estimates with a margin of error ^[1]. The ONS cautions that lower response rates have increased uncertainty, which is why some small changes are described as not statistically significant ^[1]. The census, held in 2021 in England, Wales and Northern Ireland and in 2022 in Scotland, offers fuller counts but only every ten years ^[5][6][7].

What counts as a cohabiting couple family?

The ONS counts two unmarried people living together as a couple at the same address, with or without children, as a cohabiting couple family ^[1]. A couple who live in separate homes are not included. Lone parents are counted separately, as are couples who are married or in a civil partnership ^[1].

Do cohabiting couples have the same legal rights as married couples?

No. In England and Wales, cohabitation gives a couple no general legal status, however long they have lived together ^[4]. Scotland gives cohabitants limited claims on separation or death, under the Family Law (Scotland) Act 2006, and Northern Ireland provides some protection but fewer rights than for married couples ^[4]. The 2026 consultation on reform covers England and Wales only ^[9].

How many cohabiting couples are same-sex?

About 4.9% of cohabiting couples in 2025 were same-sex couples, up from 2.8% in 2015, while the share among married couples was 0.9% ^[1]. In absolute terms, same-sex cohabiting couple families numbered about 137,000 in 2023 ^[3]. The ONS notes that the change in the share since 2015 is not statistically significant ^[1].