Moving in together can boost life satisfaction beyond the ‘honeymoon effect’

A new study from Warwick, Bielefeld University and University of Greifswald has analyzed data from 1,103 participants in the German Socio-Economic Panel (SOEP) and the UK Household Longitudinal Study Understanding Society (UKHLS) to find that life satisfaction is, on average, highest in the year after couples start living together. After that, it remains well above the level reported during single life for several years.

Professor Anu Realo from the University of Warwick, a co-author of the study, explains, “The transition from single life to a committed partnership leads to a sustained increase in life satisfaction, at least over the first years, and not just a short-lived ‘honeymoon effect.’ The results therefore challenge the traditional view that people quickly return to a genetically determined baseline state of well-being after positive or negative life events.”

The greatest gain in life satisfaction occurs at the transition from being single to being in a relationship. If the relationship began a year before moving in together, cohabitation only stabilizes the level and the positive effect lasts for at least two years (the length of time assessed in this study). The study indicates that marriage enhanced life satisfaction far more in the 1980s and 1990s than it does today, reflecting a decline in its overall importance.

“The beginning of a relationship is a turning point for life satisfaction, and a positive one. Moving in together brings stability above all. This is clearly evident from the data,” explains the study’s first author, Dr. Usama EL-Awad from the Faculty of Psychology and Sports Science at Bielefeld University. “Marriage is less important in the early years of a relationship now than it used to be, probably due to social change and the growing acceptance of non-marital partnerships.”

The study shows a clear positive connection between living in a partnership and well-being. Psychologist Dr. Theresa Entringer from the University of Greifswald and the German Institute for Economic Research (DIW) says, “What is striking is that life satisfaction improves in the same way across all groups studied with the beginning of a relationship and moving in together. The increase is independent of age, sex, income, or education.”

Overall, the results show that starting a romantic relationship and moving in together is associated with a significant rise in life satisfaction, peaking in the year of cohabitation. The additional positive effect of marriage has been absent in more recent decades, a shift that suggests that, in contemporary Western societies, cohabitation itself may now carry the symbolic commitment once conferred by marriage.

“Even in our digital age, partnerships remain central to well-being,” says the study’s senior author, Professor Sakari Lemola from the Faculty of Psychology and Sports Science at Bielefeld University. “The need for a stable partnership is deeply rooted. It appears across cultures and can also be observed in monogamous animal species such as swans, albatrosses, and penguins.”

The paper, “Mapping Life Satisfaction Over the First Years of Cohabitation Among Former Singles Living Alone in UK and Germany,” is published in the Journal of Personality.

About the datasets

The researchers used data from the German Socio-Economic Panel (SOEP) and the UK Household Longitudinal Study “Understanding Society” (UKHLS). In both studies, several thousand people have been surveyed repeatedly about their living arrangements, well-being, and other topics—in SOEP since 1984 (about 20,000 households annually) and in UKHLS since 2009 (about 40,000 households annually).

From these two large datasets, the study’s research team identified 1,103 individuals who reported living alone as singles in at least one annual survey and who entered a partnership and moved in with their partner during the following two years.

If the individuals remained with their partners—which was the case for the majority—their life satisfaction was tracked for another two years. Some of them also married during this period. The annual surveys made it possible to track changes in life satisfaction before and after these partnership transitions.