Objectives Contributing towards improving knowledge about access to health services in Colombia following health-sector reform, highlighting the main results and gaps in research. Methods Original papers were systematically reviewed through a comprehensive search and analysis of original papers published between 1994 and 2009. After selection criteria had been applied, 27 papers were included in the review. Analysis was based on Aday Aday & Andersen and Gold's theoretical frameworks, distinguishing between potential and actual healthcare access and considering the characteristics of the population, health services and insurers influencing service use. Results There was little explanatory analysis of service use applying determinant models; this was also partial (limited to geographical areas, diseases or specific groups). Likewise, only a few studies analysed contextual factors influencing service use (health policies and health providers and insures) or social actors' perspectives. The available studies did not seem to indicate increased actual access (except for subsidised system users) but, on the contrary the existence of barriers relating to population (insurance coverage, income and education) and health service factors (geographic and organizational accessibility and quality of care). Conclusions This review led to identifying important limitations in the analysis of healthcare access in Colombia and highlighted the need for further research on actual access and the better incorporation of context variables and actors' perspectives in understanding the impact of reform on health service use.