This chapter examines the subjective well-being of Japanese consumers. Since around the 1980s, subjective well-being (SWB) measures have been adopted as one of the key policy goals by countries and international organizations, alongside traditional macroeconomic indicators like Gross Domestic Product (GDP). SWB is primarily a measure of individual cardinal utility, compensating for the limitations of ordinal utility that have dominated academics in recent years. This study uses three years of survey data collected by the Japanese government and employs a linear mixed-effects model to identify the determinants of SWB in Japan. The findings reveal the following points: individuals lacking community connections tend to experience lower levels of happiness when they feel lonely; men in their 30s and 40s report lower happiness levels; and regionally, happiness is higher in the Kinki and Kyushu/Okinawa regions compared to Hokkaido (used as a baseline for comparison). These results suggest that policies aimed at reducing social isolation within communities are essential in Japan, and further investigation into the regional environment is needed. The SWB measure used in this chapter, as a dependent variable, is included in the analysis of Chap.  5 .