This final thesis deals with the topic of wages and a comparative analysis of voluntary pension insurance and systems (the so-called III pillar of pension insurance) in the United States of America (USA), Norway and Croatia. The aim of the research is to compare different aspects of these systems in order to gain insight into the differences and similarities in terms of salaries and pension benefits. In the first part of the paper, the theoretical framework and context related to wages, all its elements and pension insurance, of which it is a part, is processed. Concept III is explained in detail. the pillar of pension insurance, voluntary insurance and the system itself and its role in each of the three selected countries. A comparison of the situation in the Republic of Croatia with the other two countries was made. The concept of salary and III was investigated. column of pension insurance in Croatia, and the challenges and advantages of that system were analyzed. The review and focus is on the position of the Republic of Croatia in relation to the USA and Norway, and possible adjustments or improvements are considered. The comparative analysis covers several dimensions, including pension coverage, replacement rates, sustainability and adequacy of benefits in all three countries. The analysis identifies similarities and differences in the stages of pension insurance and assesses their impact on the financial well-being of retirees, addressing the issues of pension adequacy and income inequality among the elderly. At the end of the work, a survey of the opinion of a selected group of respondents was conducted regarding the issue of voluntary pension insurance in order to draw conclusions that are key for the further implementation and potential progress of the aforementioned system.