What constitutes as adultery in the UK?

For the purposes of getting a divorce in the UK, adultery specifically refers to the following:

• a married man having sexual intercourse with a woman other than his wife or
• a married woman having sexual intercourse with a man other than her husband.

Citing adultery as a reason for divorce

To obtain a divorce, you must be able to prove that your marriage has broken down irretrievably. You can do this by citing one of five different facts – adultery being one of them.

• Adultery
• Unreasonable behaviour
• Two years separation with consent
• Desertion
• Five years separation

In the UK, you can only cite adultery as a reason for divorce if your partner has had sexual intercourse with a person of the opposite sex. If your partner has been unfaithful with someone of the same sex, technically they haven’t committed adultery so you are unable to give this as your reason for wanting a legal separation in your divorce petition. This also applies if you’re in a homosexual relationship and your partner has a same-sex extramarital affair.

Online dating sites and apps

Many people assume that any kind of physical intimacy outside of a marriage would be seen as adultery, however adultery has to involve sexual intercourse. If you discover that your partner has been using dating apps, this does not qualify as adulterous behaviour. Even if your partner has been physically intimate with another person, it must be established that they had sexual intercourse for their behaviour to be deemed as adultery.

Living together

Further to this, to be granted a divorce on the grounds of adultery, you must not have lived together as a couple for six months or more after you discovered that your partner had been unfaithful. If you remain living together as a couple for six months or longer, you will forgo your right to give adultery as your reason for legal separation.

Is there another way to get a divorce if your partner has been unfaithful?

If you’re unable to use adultery as a reason for divorce due to its legal definition, or you’re unable to prove it, you can cite ‘unreasonable behaviour’ instead. This has a much broader definition and you can use it if your spouse has behaved in a way that you cannot reasonably be expected to live with. Inappropriate relationships with other people can, and frequently are, given as the justification for applying for a divorce. You can also take this approach if you’re in a same-sex marriage or if your partner has been unfaithful to you with someone of the same sex.

Will we get a “no fault” divorce system in the future?

The legal definition of adultery is increasingly outdated given the change in UK law over recent decades, particularly when it comes to same-sex relationships. Gay couples have been able to enter into civil partnerships since 2005 and into marriage since 2014. This has led many to call for a change in the law to address the discrimination whereby same-sex relationships don’t constitute adultery.

Many family law solicitors also hope that divorce law in the UK will move towards a ‘no fault’ or ‘no blame’ system. It’s believed that a more peaceful and less antagonistic approach to divorce is in the best interests of separating spouses, particularly where there are children involved.