Couples who live together to share the bills or who never intended to build a lifelong relationship could have a claim on each other’s wealth when they move apart, lawyers have revealed.

Furthermore, parents who give a grown-up child money towards their first home could see part of their gift handed to a boyfriend or girlfriend if the couple split up, due to the unintended consequences of new rules. The Government is consulting on proposals designed to create a safety net for cohabiting couples who split up or where one person survives their partner.

At the moment, when married couples divorce, their money, property and other assets are typically split 50-50. However, couples who live together but are not married or in a civil partnership are not afforded such rights. The concept of ‘common law’ marriage holds no weight in law.

New Ministry of Justice proposals are designed to give cohabiting couples greater protection rights over each other’s assets if they break up or if one of them dies.

Parents who give a child money for their first home could see part of it given to their partner

Partners could be told to split the proceeds of a house sale, for example, even where it is owned in one person’s name. The Government has suggested that this would only apply to couples who have been together for longer than three years or those who share children. All must show an ‘enduring family relationship’.

However, Wealth & Personal Finance has heard concerns from family lawyers that the proposals could have unintended consequences for young couples living together to save money, rather than as the start of a lifelong partnership.

Mark Chiverton, senior associate in family law at SA Law, says: ‘It could be a real grey area for younger couples, where they are each renting but it’s too expensive so they decide to live together. The challenge for policymakers is distinguishing between a genuine, long-term, family partnership, and a relationship that happens to involve you sharing a house together.’

The reforms are set to apply to those as young as 18 and will cover those at university and starting out in their careers. High rents have driven some couples to move in together at an earlier stage. The typical rent took up 44 per cent of the average salary in 2025, according to Rightmove.

Clare Radcliffe, partner in family law at Mishcon de Reya

Clare Radcliffe, partner in family law at Mishcon de Reya, says: ‘Three years when you are young and haven’t got children and are just starting out is not the same as three years when you are 35 and in a relationship. Care will be needed to ensure that the identification of potential claimants is not too broad.’

It could also have implications for parents who want to help their children when they are starting out, as there would be the potential for a boyfriend or girlfriend to make a claim on equity in a shared home.

Radcliffe adds: ‘Take the parent of a 21-year-old who gifted money to put down a house deposit so their child could save money on rent after graduating, then after a year the child’s girlfriend moved in.

‘That parent would have to be alive to these possibilities.’

In its proposed form, the law could technically allow anyone to bring a claim unless they could not have legally married the person they had cohabited with – for example, a brother and sister living together.

However, it is unlikely that a spurious claim on someone’s assets from a housemate they had never been in a relationship with would be successful.

This is because a court would seek evidence of their relationship, which would include shared bank accounts and expenses, text messages, photos and statements from people who knew them. They would have to prove what is known as ‘public awareness’ of their relationship.

That said, there could be complications for those who started off as friends but then formed a relationship, or vice versa, such as in university house shares. That’s because one partner could claim that the relationship was longer standing or more serious than it was.

The law has not changed yet and the proposals could be altered before becoming law, or even be abandoned altogether under Andy Burnham’s Government, as they were proposed before the change in leadership. The consultation ends on Friday.

Those who want to protect their finances now could consider a cohabitation agreement.

This is similar to a pre-nuptial agreement that some couples sign before getting married, and sets out what they want to happen to their finances should they separate.

Setting one up costs between £300 and £4,000, depending on how complex the case is, according to The Law Society. The consultation on the reforms also suggests couples could be allowed to ‘opt out’ of the new rules if they both agree – which could be a cheaper solution. However, is not clear how they would do this and whether it could be retrospectively applied.

Either way, Chiverton says it is a good idea to keep records of your financial contributions in a cohabiting relationship, as well as recording any gifts or loans from either party’s parents.