Part of: Divorce Specialists
If you are looking up the top causes of divorce, you may really be asking about your own marriage. Official records for England and Wales name one leading cause, called “behaviour”. It was the legal fact in 43.2% of opposite-sex divorce petitions in 2021. That was the last full year before the law changed (ONS, Divorces in England and Wales: 2021). Yet the label says far less than it seems, and since 6 April 2022 no cause is recorded at all. Our divorce specialists assist and advise at every stage.
This guide explains what the official figures show, why they only tell half the story, and what the cause can still change for you. It covers England and Wales only.
Reviewed by: Iblal Iqbal, Partner & Family Law Strategist, Kabir Family Law
Key takeaways
- Behaviour led the records. It was the fact in 43.2% of opposite-sex divorce petitions in 2021 (ONS).
- The label hid the detail. In behaviour petitions sampled from 2014 and 2015, three in four described relationship problems, and 42.2% alleged some form of domestic abuse (Nuffield Foundation, 2017).
- The records were not the whole truth. Only 29% of people on the receiving end of a fault divorce said the fact very closely matched why they separated.
- No cause is needed now. Since 6 April 2022, a statement that the marriage has broken down irretrievably is enough (Matrimonial Causes Act 1973, s.1).
- The cause rarely decides the money. A court weighs conduct only where it would be unfair to ignore it (s.25(2)(g)), so the order of your next steps often matters more.
What are the top causes of divorce in England and Wales?
The official answer comes from divorce records, which only captured one thing: the legal “fact” a spouse relied on. Until 6 April 2022, every divorce needed one of five facts (Matrimonial Causes Act 1973, s.1(2), as it stood before that date). The Office for National Statistics (ONS) counted how often couples used each one.
| Legal fact | Wives, 2021 | Husbands, 2021 | Wives, 1981 | Husbands, 1981 |
|---|---|---|---|---|
| Behaviour | 48.1% | 34.8% | 43.5% | 10.3% |
| Two years’ separation, with consent | 27.6% | 34.8% | 22.9% | 31.8% |
| Five years’ separation | 15.1% | 22.5% | 5.8% | 12.1% |
| Adultery | 8.7% | 7.5% | 25.1% | 43.4% |
| Desertion | 0.3% | 0.4% | 2.3% | 2.1% |
Source: figure 3 of the ONS 2021 bulletin. Columns may not total 100%, because a few cases used two facts.
So, on paper, the top causes of divorce was behaviour, then the two separation facts, then adultery. Desertion was rare. Our guide to the old grounds for divorce explains how each fact worked.
Here is the risk. Many people assume the fact on a divorce form decides who keeps what, or where the children live. Practitioners told the Government this belief was common and often went uncorrected without advice (Ministry of Justice, 2019).
What is the leading cause of divorce, and has it changed?
On the records, behaviour has been the leading cause of divorce for wives for over 40 years, and for husbands in most years since 2006 (ONS, 2022 bulletin). In the 1980s and 1990s, husbands most often relied on adultery, and from 1999 to 2005 on separation with consent (ONS, 2019 bulletin). Even in 2023, behaviour was the fact in 57.5% of the opposite-sex divorces finalised under the old rules (ONS, 2023 bulletin).
Meanwhile, adultery faded. The Nuffield Foundation’s Finding Fault? study found it fell from 30% to 12% of all petitions between 1975 and 2015, while behaviour rose from 26% to 46%. Part of that shift may be practical: adultery only covered sex with someone of the opposite sex, whereas any infidelity could be cited as behaviour (Government response, 2019). Our guide explains how an affair can affect divorce proceedings today.
That matters if an affair is part of your story, because blame tends to make everything harder. In the same study, 31% of people on the receiving end of a fault divorce said it made sorting out the finances harder.
Why don’t the records show the real cause of a divorce?
Because couples often chose the fact for speed, not accuracy. Behaviour or adultery could be used once the marriage had lasted a year, while the separation facts meant waiting two or five years (Government response, 2019).
The Nuffield researchers found that England and Wales did not have unusually high levels of infidelity or misbehaviour. Instead, people used fault to avoid those waits, and the courts made no judgement on whether the allegations were true (Nuffield Foundation, 2017).
- 29% of people on the receiving end of a fault divorce said the fact used very closely matched why they separated.
- Twice as likely: applicants were twice as likely as the other spouse to say the fact reflected the breakdown.
- 43% of those named as at fault disagreed with what their spouse had cited.
The Government agreed in 2019, saying the old process encouraged allegations that might bear little relation to why a marriage really ended. So in an undefended case, the petition was not a judge’s finding about the cause of the divorce. If you are relying on an old petition, or worried about what your spouse might say, know what it can and cannot show today.
What are the main causes of divorce behind the legal labels?
The same study looked inside the behaviour label. It read 135 behaviour petitions issued in 2014 and 2015 and noted what each one alleged. Many raised more than one issue, so the figures overlap.
- Relationship problems: 74.8% (the study calls these interpersonal problems).
- Some form of domestic abuse: 42.2%, using the Government’s wider definition.
- A relationship with someone else: 26.7%.
- Money problems: 20.0%.
- Sexual problems: 18.5%.
- Physical violence towards the spouse who applied: 14.8%, down from 64% in the 1980s.
- Mental health, including a lack of support: 14.1%.
- Drink or drug misuse: 10.4%.
This is a small sample of petitions written to fit a legal test, so treat it as a guide, not a survey. Still, the Government cited it, and it shows what sat behind the most common cause of divorce on the records.
Some of these causes bring risks of their own. If money problems were part of it, an agreement about money only becomes legally binding once a court approves it as a consent order. Until then, a court cannot enforce it if problems arise later (GOV.UK).
Why do people get divorced now that no cause is recorded?
People still divorce for the same mix of causes, but the law stopped asking. Since 6 April 2022 (SI 2022/283, reg. 2), either spouse, or both together, can apply by stating that the marriage has broken down irretrievably. The court must treat that statement as conclusive (Matrimonial Causes Act 1973, s.1).
The Government said the change ended the need for separating couples to blame each other (GOV.UK, 2022). Many consultation responses argued there is often no single cause. Our guide to no-fault divorce explains the current process.
As a result, the cause of divorce is fading from the statistics. In 2023, 74.2% of divorces went through under the new law (ONS, 2023). Nobody can apply until the marriage has lasted a year (s.3). GOV.UK says a divorce normally takes at least 7 months, and the application fee is £628 (GOV.UK).
Because nobody asks why, it is easy to treat the application as the whole job. It is not. GOV.UK says that if you want a legally binding arrangement for money and property, you must apply for it before you apply for the final order (GOV.UK).
Does the cause of your divorce affect money or children?
Usually far less than people expect. A court dividing money weighs factors such as each person’s needs, their ages and the length of the marriage. Conduct counts only where it would be unfair to ignore it (Matrimonial Causes Act 1973, s.25(2)). As the Nuffield researchers put it, the law does not let fault shape arrangements for children or money, other than in extreme circumstances.
For children, the court’s paramount consideration is the child’s welfare (Children Act 1989, s.1). Where a cause touches a child’s safety, it becomes a welfare question, because in a disputed case the court must consider any harm a child has suffered or is at risk of suffering.
The costly mistakes tend to come from the order of steps, not the cause. GOV.UK says it is usually simpler to ask a court to approve a consent order before the final order, because asking afterwards may have financial consequences, particularly for pensions.
Worried that the cause of your break-up will count against you, or be ignored? Book a free initial consultation, and one of our specialists will give you initial advice on how it could affect your case.
What if abuse is the cause of your divorce?
Abuse is not always physical. The law’s definition of domestic abuse includes threats, controlling or coercive behaviour, economic abuse, and psychological or emotional abuse, as well as physical or sexual abuse (Domestic Abuse Act 2021, s.1). In the Nuffield sample, 42.2% of behaviour petitions alleged some form of abuse. If money was used to control you, our guide to financial abuse and family law explains how courts can respond.
Abuse also changes the safest order of steps. GOV.UK says you can make a joint divorce application only if you both agree and you are not at risk of domestic abuse. If you are in immediate danger, call 999 and ask for the police (GOV.UK). When abuse is the cause of a divorce, get advice before you tell your spouse you plan to leave, so you can plan each step safely.
Causes of divorce checklist: where do you stand today?
You no longer need to prove a cause, but the cause of your divorce can still shape what you do next. Tick what is already true. It will not give you a verdict.
There is no score. Anything you cannot tick yet is worth raising before you take the next step.
The calls a checklist can’t make for you
- Whether anything in your marriage is conduct a court could not fairly ignore when it divides money.
- Whether you need protection first, before anything else happens.
- What to settle before the final order, so the home and pensions are not left exposed.
- How to agree arrangements for the children when trust has broken down.
These turn on your own facts, and are far easier to get right before you apply than afterwards.
Book a free initial consultation
One of our specialists will give you initial advice on your situation.
Frequently asked questions
What are the 5 most common causes of divorce?
On the ONS records for 2021, the five legal facts ranked: behaviour, two years’ separation, five years’ separation, adultery and desertion. Behind the behaviour label, a 2017 Nuffield Foundation study found relationship problems, abuse, relationships with someone else, money problems and sexual problems came up most often.
What is the #1 divorce cause?
On paper, it is behaviour, the most common fact for wives for over 40 years and for husbands in most years since 2006 (ONS). However, it was a legal label: in a 2017 study, only 29% of people on the receiving end of a fault divorce said it very closely matched why they separated.
What is the biggest cause of divorce in the UK?
The ONS figures cover England and Wales only. There, the biggest recorded cause was behaviour, the fact in 57.5% of the opposite-sex divorces finalised under the old law in 2023. Divorces started since 6 April 2022 record no cause at all.
Why do marriages fail after 40 years?
The official records cannot say, because they never captured the real cause. The law does make one thing clear: a long marriage changes the money questions. A court must consider each person’s age, the length of the marriage and any benefit, such as a pension, that a spouse may lose through the divorce (Matrimonial Causes Act 1973, s.25(2)).
Do I have to prove why my marriage ended?
No. Since 6 April 2022, you only need to state that the marriage has broken down irretrievably, and the court must treat that statement as conclusive (Matrimonial Causes Act 1973, s.1). You can apply alone or with your spouse, as long as the marriage has lasted at least a year.
Recognise your marriage in these? Get advice before you decide what’s next
Whatever the cause, the order of your next steps matters, especially for pensions. Book a free initial consultation and one of our specialists will give you initial advice tailored to your circumstances. You can also read more about our divorce specialists.
Expert Tip
People often want to explain why their marriage ended, or to see it written down. Since April 2022, the divorce itself needs no cause at all. Where the cause still matters, such as abuse, or conduct a court could not fairly ignore, it matters in the money and children arrangements, and timing counts. So before you apply, or reply to your spouse, get advice on what to raise and when.
Garry Steedman, Family Law Consultant (Divorce, Children & TOLATA)
