The same UK parental leave package nets £10.1 billion or costs £6.3 billion, depending on one line item

A University of Bath report published on October 13, 2026 values a redesign of UK parental leave at a £10.1 billion net social gain when life-satisfaction effects are counted over ten years. Leave the money value of wellbeing out of the same model and the result is a £6.3 billion net cost.

A package with six parts

The report is called "Sharing the load: Costs and benefits of parental leave reform". It comes from the university's Institute for Policy Research and is signed by Dr Joanna Clifton-Sprigg, Dr Alistair Hunt, Tiffany Choeung and Ciaran Hay.

The package they test combines 18 weeks of maternity leave paid at 90% of average weekly earnings, six weeks of non-transferable paternity leave at 90%, 21 weeks of paid shared leave and 13 weeks of unpaid shared leave. It adds day-one access to paid leave and equivalent provision for self-employed parents.

The starting point is lopsided. According to a University of Bath release of June 30, 2025, fathers in the UK are entitled to just two weeks of leave, often poorly paid. Statutory maternity and paternity pay rose from £187.18 to £194.32 a week, according to an academic commentary on The Conversation, which adds that this is less than half the National Living Wage.

Two details of authorship matter for a reader weighing the numbers. The report is based on Tiffany Choeung's dissertation and builds on the institute's earlier report on improved leave for fathers. Clifton-Sprigg and Hunt received University of Bath funding, and the authors thank Working Families and the Fatherhood Institute for feedback on the policy design. The Fatherhood Institute's deputy chief executive, Dr Jeremy Davies, heads its campaign for six weeks for dads, according to the 2025 release.

Where the £10.1 billion comes from

The report names its biggest line on each side. The largest quantified cost falls on employers, through reorganisation and temporary cover. The largest quantified benefit comes from parental wellbeing.

So the ledger has employer cover priced in pounds on one side, and parents' life satisfaction, converted to pounds, on the other. The second entry carries the total.

The report is open about how much. The £10.1 billion figure assumes average take-up and a ten-year wellbeing effect. Shorten the effect to five years and the net gain falls to £1.9 billion. Exclude monetised wellbeing and the model shows a £6.3 billion net cost.

Nothing here is hidden, and the authors do not present it as settled. A reader who sees only the headline figure would miss that the report's own summary carries both the gain and the cost, and that the gap between them depends on how the wellbeing line is valued. Their recommendations are that policymakers should assess parental leave as a package, make uncertainty explicit and improve UK evidence on take-up, employer costs, family wellbeing and longer-term labour-market outcomes. In plain terms, the four inputs the model leans on hardest are the four the authors say the UK has too little data on.

Three UK estimates, three different questions

The Bath figure is not the only large number in circulation, and the numbers do not add up to one answer.

The June 2025 Bath report on six weeks of father-reserved leave put the net social benefit at up to £12.8 billion annually. A later Bath analysis of a six-week paternity allowance for self-employed and "worker" fathers, summarised in a university announcement of July 8, 2026, found benefits worth nearly £3 billion per year.

King's College London has published a scoping review that forecast a net £2.68 billion a year for six weeks at 90% of earnings once fully established. That figure is the output of more mothers working (£5.5 billion) minus an estimated £2.8 billion for fathers' time away from work.

These are different packages, different horizons and different things being counted. King's counts extra economic output net of the fathers' absence. The 2025 Bath report counts net social benefits. The 2026 Bath report adds a wellbeing valuation and then shows what happens without it.

A fair reading holds all three in view: each model finds the reform worth more than it costs under its own assumptions, and the assumptions carry the size of the gap.

The 2025 release adds a point of comparison from abroad. It says international evidence from Quebec, Sweden and Iceland shows that dedicated, well-paid leave for fathers leads to greater sharing of care, earlier returns to work by mothers, and long-term equality gains. That is a claim about direction. The pound figures are where the models part company.

What happened elsewhere when fathers got leave of their own

The King's review is the nearest thing to a behavioural test in this week's material. It covers 33 studies of paternity and parental leave reforms across 11 OECD countries, in Europe, Canada and the US. Most compared families affected by a policy change with similar families who were not, which helps separate the reform from changes that would have happened anyway.

The pattern it reports is about who ends up doing the work. Fathers are far more likely to take leave when it pays a substantial share of their wages and is theirs alone, and when it is lost if unused. Fathers who took leave subsequently did more childcare and housework, in some studies for several years afterwards.

In Quebec, the 2006 reforms introduced five weeks of leave reserved for fathers, paid at around 70% of earnings. The proportion of fathers claiming leave rose from 21% to 74%, and the share of mothers in the labour market and working full time rose by around five percentage points. Fathers affected by the reform were still doing more unpaid work at home one to three years later.

Iceland offers the relationship angle: couple separations dropped by 12 percentage points after the country added four weeks of non-transferable "daddy quota". A US study attributes a fall in parental separation from 7.5% to 5.6% to parental leave. Spain, which equalised leave at 16 weeks for each parent in 2021, saw paternal uptake rise from 46% to over 75%, according to The Conversation commentary.

The review states its limits itself: "Results were not identical across every country or family." Effects depended on how much the leave paid, whether it was reserved for fathers, how families used it and what each study measured. Some of the evidence on wellbeing was not as strong as the evidence on mothers' employment.

Professor Heejung Chung, who directs the King's institute, put the accounting problem directly: "Paternity leave is still too often treated simply as a bill for government and employers." A recent Reflets brief covered a psychologist's case that paternity leave is child development, which also rests on correlational research.

What UK parents say they want, and the review under way

A second Bath policy brief, also published on October 13, 2026, reports a conjoint survey experiment with 2,501 UK adults aged 18 to 45 who have, or plan to have, children. Respondents backed more generous provision for both parents.

Extending maternity leave paid at 90% of earnings from six to 26 weeks raised policy support by 27.4 percentage points. For fathers and partners, pay mattered more than length: moving from statutory pay to 90% of earnings raised support by 18.9 points, while extending leave from two to six weeks raised it by 7.8 points. A survey experiment measures support for designs on paper, not what families end up doing, and the respondents were all parents or prospective parents.

What families do now is documented elsewhere. Shared Parental Leave, introduced in April 2015 to let couples split care, has not, on average, led to greater take-up or longer leave by fathers, according to Bath research cited in a July 2026 university announcement. The Conversation commentary puts use at fewer than two in every 100 eligible fathers. It adds that the system requires mothers to give up part of their own entitlement rather than giving fathers independent rights.

The Bath 2025 release says women's employment in the UK drops by 15 percentage points around childbirth, while men's work patterns remain unchanged. The Office for National Statistics analysis cited by The Conversation puts the fall in mothers' monthly earnings at an average of 42% in the five years after a first child, around £1,051 a month.

The policy context is partly settled. From April 6, 2026, paternity leave and unpaid parental leave became day-one rights, but statutory paternity pay remains subject to 26 weeks' service, so many new starters still take leave unpaid, the commentary notes. Dr Clifton-Sprigg has said that parents decide about leave, childcare and work together: "Parents make decisions about leave, childcare and work as a package, so reforms need to be designed with those interactions in mind."

The King's College London report has been shared with ministers involved in the ongoing parental leave review.

Sources

• Sharing the load: Costs and benefits of parental leave reform, University of Bath Institute for Policy Research, October 13, 2026
• More time, better pay: What current and prospective parents want from parental leave, University of Bath Institute for Policy Research, October 13, 2026
• Six weeks for Dads: New report calls for overhaul of UK paternity leave offer, University of Bath, June 30, 2025
• Bath research featured in new Parliamentary briefing on parental leave and childcare policy, University of Bath, July 8, 2026
• Six weeks' paid leave for fathers could boost the economy, King's College London