Britain is facing a family crisis that politicians do not talk about nearly enough. Birthrates are now the lowest since records began. More and more young people are delaying having children – or deciding they simply cannot afford to have a family at all. When you look at the cost of raising children today, it is easy to see why.

Families are feeling the pinch. Many now spend more than £250,000 raising a child to the age of 18. For many parents, the pressure starts long before school, with childcare costs that have risen far faster than wages for years.

This government’s expansion of 30 hours funded childcare in England has made a real difference. Eligible families using 30 hours can save on average £8,000 a year per child, and more than 530,000 families are already benefiting.

This is proving nothing short of transformative for thousands of families, getting costs back to 2005 levels for a child in a part-time place. A full-time place costs more than a third less than it did last year.

My department alone is putting in a record £9.5bn this year, and across all government programmes we fund more than 80% of all childcare spending in the country. That is on top of school-based nurseries, Best Start Family Hubs and free breakfast clubs, all designed to back families at every stage.

Yet despite that unprecedented investment, too many parents are still not feeling the full benefit. The vast majority of nurseries and childminders are doing a brilliant job – but we have to ask hard questions every time we hear stories of families hit with hidden charges, restricted hours or excessive deposits that bear no relation to what parents are actually paying. That is not what this investment was meant to deliver.

And there are bigger forces at work too. In recent years the number of nurseries backed by private equity and investment firms has doubled. For every £5 spent at an investment-backed nursery in England, more than £1 ends up as profit – double what other private nurseries make and seven times more than non-profits. Their debts have also ballooned, raising real questions about what happens to families if the business model fails. Parents have every right to ask whether some investors are putting profits before their children – and this government intends to find out.

That is why I have asked the Competition and Markets authority (CMA) to look into whether the childcare market is working fairly for parents.

We are interested in hidden fees, unfair charges and practices that mean parents end up paying extra just to access the funded childcare hours they are entitled to.

We’ve been clear with the CMA that we want it to look at the role private equity is playing in childcare, including whether these investors are driving up costs or creating instability for families who rely on local nurseries. Because this is about more than just childcare bills. It’s about fairness and transparency.

Families are facing shock fees, confusing bills, unexpected extra charges and demands for deposits they can barely afford. Parents are left wondering why accessing their funded childcare entitlement still comes with so many extra costs.

Today we are also launching a new service on the Best Start in Life website in England so parents can clearly see what childcare support they are entitled to, estimate costs and find providers in their area.

High costs affect whether parents can afford to go back to work. They affect household budgets already stretched by the cost of living crisis. But childcare is only part of the picture. The decision to start or grow a family is shaped by a whole range of pressures – the difficulty of getting on the housing ladder, the insecurity of renting, the challenge of balancing work with family life. That is why this government is acting on all fronts: building more homes, strengthening renters’ rights and making workplaces more family-friendly. Because when families feel financially secure and supported, they are more able to invest in their futures, including having the children they want.

Affordable childcare is not a luxury. It helps children thrive, supports parents back into work and gives families confidence to invest in the future.

It should be the ambition of every government to enable people to live the lives they want to lead: better standards of living, happier, more fulfilled family lives – including having a family if that’s what couples want. These are the principles I believe in. It is not only essential to the future of our whole society but also to the promise of what it means to live in this country. No parent who works hard and plays by the rules should feel priced out of family life.

• Bridget Phillipson is secretary of state for education, women and equalities

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