This study has three principal aims: to classify consumers by their retirement preparation planning and behavior; to examine the financial status of retirement preparation in each country; and to find ways to help consumers effectively secure financial sustainability after retirement by practicing retirement preparation. Adopting the planner–doer model, consumers were classified into four types: ‘indifferent,’ ‘just planner,’ ‘just doer,’ and ‘ideal doer.’ This study used data collected by Korea Life Insurance Association to compare the level of retirement preparation in Korea, Japan, Germany, the U.S., and the U.K. The data were analyzed using the chi-square test, analysis of variance (ANOVA), and binary logistic regression analysis. The major findings are three-fold: first, the largest percentage of consumers in every country were ‘just doers’; second, ‘ideal doers’ are older than the other types, but have a low expected retirement age and high level of retirement preparedness; and third, ‘ideal doers’ demonstrated distinct variations in their characteristics in different countries. These findings indicate the need to help consumers recognize the necessity to prepare effectively for financial sustainability in their post-retirement lives; this requires the development of policy and gradual education programs, including effective practical suggestions.