ONS releases latest UK family data, legal expert responds

The latest “Families and Households, UK” release shows that the number of families living in the UK has increased 15% since 1996. The report explores figures across married and unmarried couples, families with and without children, single parents and cohabitating couples.

Commenting on the findings, Jenniffer Brunt, Head of Family Law at Slater and Gordon, says the figures clearly demonstrate a shift away from a single “traditional” family model.

“It’s interesting to understand what's behind the figures, and the story it tells. It’s clear from first interpretation that there is less of a ‘standard’ family type in the UK,”

Married couples remain the most common family type, accounting for around 65% of all UK families. However, the data also shows a notable change in how many of those families include children.

Families without children now stands at 8.2 million, nearly matching, and in future likely to exceed, the 8.5 million with dependent children. Overall, just 43% of families have dependent children.

Among those with children:

• 45% have one child
• 41% have two children
• Only 14% have three of more children

“These figures likely reflect broader social and economic pressures,” Jenniffer adds. “Financial considerations, including the ongoing cost‑of‑living pressures, can put limits on family size. For others, particularly women, career priorities may also play a greater role in deciding whether or when to have children.”

The data also highlights the reality of single-parent families. For nearly 3.2 million families with dependent children are lone-parent families, where a striking 84% are lone mothers (at 2.7 million).

Jenniffer explains, “In custody rights, unmarried mothers automatically have parental responsibility under UK law. For fathers, this is dependent on factors such as their name being on the birth certificate of their child. However, the number of lone-parent fathers has increased over time, reflecting a justice system that is increasingly focused on the best interests of the child following separation or divorce.”

One of the greater changes for family dynamics is the rise in cohabitating families. There are now 3.5 million families cohabiting, representing 18% of total UK families, with numbers continuing to rise gradually year on year.

Jenniffer notes that financial pressures and shifting social attitudes are driving this change. “For many couples, cohabitation is a practical choice rather than a stepping stone to marriage,” she says. “We’re no longer in a society where marriage is needed to access financial or legal benefits.”

She adds that proposed cohabitation law reforms expected in spring 2026 could further reshape family law, offering greater legal clarity and protection for cohabiting couples if their relationship ends.

“These reforms may introduce improved rights around property, finances and long‑term security for families who choose to live together but not marry.”

Jenniffer concludes, “The data is a fantastic way to draw upon how the family law is being adapted to meet the shifting needs of UK family types. Using such reports enables us as family lawyers to anticipate what trends are emerging and understand the different dynamics of different household types.

“Ultimately, every family situation is different and there is no ‘one-size-fits-all' approach. It is important to us as family lawyers that legal advice reflects the realities that different families are experiencing, and ensure such outcomes are fair, practical and the best solution for all parties involved.”