Using a micro dataset from labour force survey of Turkey and employing a multinomial logistic regression, this paper examines the determinants of mere overeducation, mere field of study mismatch and full-mismatch (who are both overeducated and field of study mismatched simultaneously). The target group consists of full-time wage-based employees who graduated from higher education and are aged 20–65. The determinants of mismatch are analysed under four variable groups which are labour market context, demography, field of study and job-specific characteristics. In line with the earlier empirical evidence, we find that the unfavourable economic conditions at the time of entry into the labour market might affect the behavioural pattern of individuals while searching for a matching job. Moreover, the sharp increase in university graduates increased further the fierce competition for the limited jobs available in the labour market, and resulted in a high likelihood of mismatch especially for the recent graduates. In sum, the estimation results yield that any mismatch category is responsive to those determinants where fully-mismatched employees are more responsive. Hence, we propose that the policy implications should better focus on the full-mismatch category.