Long term cohabiters much less likely to say ‘I do’

We launch our Marriage Week campaign, and the publication of the book Commit or Quit – The Two Year Rule and Other Rules for Romance, with a striking new piece of research from Harry Benson of Marriage Foundation and Professor Stephen McKay of the University of Lincoln.

These are the key findings:

  • The longer a couple cohabits, the less likely they are to get married.
  • Living together for a long period of time makes little difference to the likelihood of a couple staying together – but increasingly diminishes the chances of them getting married.
  • Couples are most likely to get married or split up in the 2nd or 3rd year of living together.
  • Couples who have lived together for 7 years or more are more likely to split up than marry.

As an increasing number of weddings are cancelled or postponed – due to lockdown restrictions – many engaged couples will end up living together longer before marrying. However, new research shows that the longer couples live together without tying the knot, the less likely they are to get married at all. The new report has been released to coincide with the publication of Harry Benson’s new book Commit or Quit on 11 May, at the start of National Marriage Week 2020 (11-17 May 2020).

Harry Benson from Marriage Foundation and Professor Steve McKay from the University of Lincoln analysed data from the British Household Panel Survey for 25,000 adults who started cohabiting between 1980 and 1990, looking at the outcomes of their relationship up to the year 2000. They discovered that, no matter how long couples had been in a relationship, 4 out of 10 cohabiting (unmarried) couples split up during the 10 years after they moved in together. However, it was notable that the longer a couple lived together, the lower the likelihood became of them getting married in the future – 5 out of 10 couples who had lived together for up to a year went on to marry, compared to 3 out of 10 couples who had lived together for 10 years.

The report also found that, while the majority of couples from this group who married were still together 10 years later, only a minority of the couples who didn’t marry were still together 10 years later. This indicates that couples who marry after a period of cohabitation are more likely to stay together than couples who choose to carry on cohabiting rather than to get married.

Interestingly, the data showed that the length of time that a couple had lived together had no direct correlation with the likelihood that they would stay together in the future if they did not marry. However, it was notable that couples who had lived together for longer and did decide to marry after 5 or more years together were more likely to stay together in the future. For couples who had lived together for less than a year, the chances of staying together for the next 10 years were 75% if they did get married and just 23% if they didn’t get married. For couples who had lived together for 8-9 years, the chances of staying together for the next 10 years improved to 95% if they did get married and to 42% if they didn’t get married.

The report also showed that the likelihood of a couple either getting married or splitting up was at its highest during the second or third year of a couple living together.

Harry Benson, Research Director for Marriage Foundation and author of Commit or Quit, commented:

‘For many young couples, moving in together seems like such a good idea. But our research highlights the very real risks: that your odds of staying together don’t ever improve with time but your odds of making a really clear long-term commitment to one another actually deteriorate with time. So my advice to all young couples is the same advice I give my children. If you want reliable love and you’re going to move in together, you need a clear plan to make sure you don’t end up heartbroken or stuck. Remember the two-year rule and either commit or quit.’

Sir Paul Coleridge, founder of Marriage Foundation and former high court judge, added:

‘When we are considering our physical health – especially during a pandemic – it seems we are more than happy to ‘follow the science’, ie. be guided by the research. But when it comes to the critically important matter of our emotional health, we ignore the research and prefer guidance by guesswork and instinct. Over and over again, the research shows that, however superficially attractive informal cohabitation may appear, it is fraught with long term risk. Not only is it three times more likely to fail than marriage, but now we learn that for those who do stay together for three years, the chances of permanent commitment declines from then on. For couples in that situation, Harry Benson’s starkly simple two-year rule ‘Commit or Quit’ should surely be taken very seriously.’


Here you can download the Research Briefing Paper as a PDF and the Press Release where it is available.

Media Links

Sunday Times – The two‑year itch: couples hit marry or break up decision at 24 months – A study of 25,000 British couples says ‘a major relationship transition’ for cohabiting partners usually comes within three years of living together

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