The demand and supply of tertiary workers contribute to shaping their earnings advantage. The expansion of tertiary education has been accompanied by a decrease in the earnings advantage of tertiary-educated younger and older workers in many OECD and partner countries. Tertiary-educated workers reap the largest advantage in countries where few adults have completed tertiary education. Older tertiary-educated workers benefit from both their relative scarcity among their generation and their longer professional experience, resulting in a higher earning advantage than their younger counterparts. It is difficult to say whether younger tertiary educated workers will achieve the same earnings advantage over time that the older generation currently enjoys. However, a formal qualification is not the sole assurance of higher earnings: higher skills lead to positive financial outcomes across all educational attainment levels.