More and more people are choosing to live together, buy property together and have children without getting married. More than 40% of British children are now born outside marriage. But what happens if these couples split up? While unmarried parents are involved in three out of four family breakdowns, this huge social shift has not been followed by a change in the law.

There is no such thing in English law as a ‘common law wife’ (or husband). Many couples wrongly believe that they will automatically qualify for some protection under the law if their relationship breaks down.

But their relationship with one another is not recognised as having any legal standing, and they have no special status in the eyes of the English legal system. The law effectively treats them as separate individuals with no rights or liabilities to each other if the relationship ends.

For such couples, this has far-reaching consequences for their home, their children and their finances.

The home

Unlike married couples, unmarried couples have no basic rights to their partner's property or to maintenance if they split up. Basically what is his is his, what is hers is hers, and what is jointly-owned needs to be divided.

If a house is bought in joint names, it should be split accordingly on separation, and either party can force a sale of the property to realise their share. If the parties are contributing unequally to the purchase price, or to payments on the property, for example if he is paying 70% and she is paying 30%, this should be reflected in the amounts they take away with them.

If the property is in the sole name of one party, it remains that person's property on separation, unless the other party can establish that there was an intention that they would be entitled to a share in the property. Proving this can cause much stress, expense and frustration.

Children

The mother is the only adult who has any automatic rights in respect of the couple’s children. She alone will have parental responsibility for them, which covers all aspects of their welfare and upbringing. However since December 2003 an unmarried father can acquire similar rights if he registers the birth of the child jointly with the mother.

If an unmarried couple split up, the mother will automatically have the right to look after her child, and the father could not challenge her unless they have entered into a Parental Responsibility Agreement or he has a court order in his favour.

Death

If one of the couple dies intestate, i.e. without having made a will, their estate will pass to their immediate family (except their house if they own it together).

An unmarried partner will not even be entitled to administer the deceased partner's estate, as they are not related.

Finances

Unmarried couples have no rights to each other’s pension if one of them dies, and for inheritance tax purposes the taxman treats them as individuals even if they have been together for years and hold their assets in joint names. While there is no inheritance tax between husband and wife, if one unmarried partner dies, all their estate above £263,000 will be taxed at a rate of 40%. From the 2005-2006 tax year this threshold rises to £275,000.