A study published in February 2026 in the International Journal of Behavioral Development suggests that the ideal age for couples to move in together, leading to increased life satisfaction, is primarily after the age of 50. Researchers led by Iris V. Wahring and Denis Gerstorf analyzed longitudinal data from 2,840 adults in the Health and Retirement Study, a large American survey following participants over several decades. Their findings indicate that moving in together, whether or not accompanied by marriage, is associated with an increase in life satisfaction. However, marriage alone, when a couple was already living together, did not show a significant effect. The study found that the move to a shared life leads to a measurable increase in life satisfaction over two years, regardless of gender, exact age within the sample, or the level of emotional support previously received. The researchers noted that the effects of relational transitions did not vary according to gender, age, or emotional support. According to the socio-emotional selectivity theory, as people age, they prioritize emotionally significant relationships. Social networks may shrink, but the bonds become deeper. Cohabitation becomes an emotional choice rather than a logical step in the romantic journey. At 28, living together may respond to practical or social logic, while at 62, it is often a carefully considered choice centered on the quality of the relationship. The study does not suggest that moving in together at a younger age is a mistake, but it indicates that the benefits in terms of life satisfaction are not automatic or immediate. At 18 or 20, personal identity is still under construction, and the twenties correspond to a phase of intense exploration. Moving in together too early can sometimes accelerate a form of fusion that limits individual exploration, potentially leading to financial or emotional dependence, isolation from the social circle, or a move due to convenience rather than a real relational choice. The study highlights that it is not the status of cohabitation that increases satisfaction, but the quality and meaning of the transition. Key psychological indicators to determine if it is the right time to live together include ensuring the decision is not a solution to a problem, maintaining individual autonomy, having tested daily life through ordinary periods, and making the decision based on desire rather than external pressures. The study suggests that after 50, cohabitation is more of an intentional act than a necessary step, which may explain the increase in satisfaction.