Two statistical agencies counted same-sex couples in April and warned about the numbers

Two national statistical offices published fresh counts of who lives with whom in April 2026, and both attached warnings to the parts of the count that describe same-sex couples.

On 17 April 2026 the Office for National Statistics released its bulletin Families and households in the UK: 2025. It put the United Kingdom at 19.9 million families and 8.6 million people living alone, or 29.5 per cent of households. Nearly half of the people living alone, 49.6 per cent, were aged 65 and over, and 63.9 per cent of that older group were women.

The figure that moved most was civil partnerships. The ONS counted about 216,000 civil partner couples in 2025 against about 48,000 in 2015, lifting them from 0.3 per cent of all families to 1.1 per cent. The bulletin places most of that increase after 2020 and links it to the legislation that opened civil partnerships to opposite-sex couples from 31 December 2019. An institution built in the United Kingdom for same-sex couples has grown mainly because different-sex couples started using it.

Same-sex couples appear elsewhere in the same release in much smaller numbers. Same-sex married couples were 0.9 per cent of all married couples, in a country where same-sex marriage has been available since 2014. Among the 3.5 million cohabiting couple families, who are 17.6 per cent of all families, same-sex couples were 4.9 per cent in 2025 against 2.8 per cent in 2015.

Those percentages rest on a household survey whose sample has thinned. The bulletin records that lower achieved sample sizes in recent years have increased uncertainty, with sizes now improving under the ONS Survey Improvement and Enhancement Plan. The same weakness is stated more bluntly in the ONS bulletin Sexual orientation, UK: 2024, published on 9 December 2025, which found 2.1 per cent of adults, about 1.2 million people, identifying as gay or lesbian, and 1.6 per cent, about 855,000, as bisexual, for a combined 3.7 per cent or 2.0 million, against 93.4 per cent or 50.7 million heterosexual or straight. Those estimates are official statistics in development rather than accredited official statistics. They are published with coefficient of variation bands running from A, precise, to D, unreliable for practical purposes, and with the caution that estimates of levels should be treated carefully while estimates of percentages remain more robust.

Sixteen days before the London release, on 1 April 2026, the United States Census Bureau published an analysis by Nestor Hernandez and Barbara Pham drawn from American Community Survey one year estimates. It counted about 1.4 million same-sex couple households in 2024 against about 777,000 in 2005, nearly a doubling across nineteen years, with 2020 left out because of pandemic collection problems. Of the 2024 total, about 836,000 were married couples, 0.6 per cent of all United States households, and about 551,000 were unmarried, 0.4 per cent. Female same-sex married households rose from about 178,000 to about 450,000 over the period, while male ones rose from about 214,000 to about 386,000, so women now make up the larger share of a category that men once dominated.

The American figures also carry money in a way the British ones do not. Median annual household income was 108,500 US dollars for female same-sex couples and 140,500 US dollars for male same-sex couples. Both partners were employed in 60.8 per cent of same-sex married households against 49.8 per cent of opposite-sex married households. The Bureau notes a design limit that matters here: the survey records how each household member relates to the householder, which can leave some cohabiting couples uncounted.

The two agencies are measuring the same thing by different means and reaching different kinds of confidence. Britain is inferring national family structure from a survey with a response problem it has publicly conceded. The United States is inferring it from a very large survey with a relationship question that its own authors say can miss people. Neither is a census. Australia does use a census, and the Australian Bureau of Statistics counted 23,914 same-sex marriages in its release of 28 June 2022, alongside 5,552,973 couple families and 1,068,268 lone parents, but that snapshot is now five years old.

A companion Census Bureau piece published on 27 April 2026, using the Current Population Survey Annual Social and Economic Supplement, shows how much richer the analysis becomes when the sample is large. It reports 5.1 million couples in which the man is ten or more years older than his partner against about 1.3 million where the woman is, and finds that 36 per cent of couples without children earn within 5,000 US dollars of each other, falling to under 10 per cent once a child is in the household. That analysis covers opposite-sex couples only.

What is not yet known is how much of the British civil partnership surge belongs to same-sex couples, because the headline figures do not split the 216,000 by couple type. Nor is it known whether the ONS sample recovery will revise the same-sex cohabiting series up or down when the next edition lands, a date the ONS has not announced.