This thesis explores inequalities in healthcare use related to immigration in Europe, providing insights into disparities between immigrants and native-born individuals. In Chapter 1, I use survey data to investigate self-reported unmet needs for care among native-born individuals and immigrants across 14 European countries. Results show that first- and second-generation immigrants, as well as non-citizens, are more likely to forgo care, especially those of non-European origin. Language barriers, religiosity, and health insurance coverage are key factors contributing to these disparities. In Chapter 2, I analyse disparities in medication use for cardiovascular risk factors among immigrants and native-born individuals. By using Spanish administrative data, I assess the likelihood of receiving prescriptions for antidiabetic and anti-hypertensive drugs, and of undergoing glycemic and blood pressure checks. The analysis is stratified by different levels of medical need and controls for socioeconomic status, diagnoses, and biometric data. Results indicate that immigrants are less likely to receive these medications, especially among patients with higher needs. In Chapter 3, I examine disparities in mental health treatment among native-born and immigrant groups in Spain, focusing on prescriptions for anxiolytics and antidepressants. I find that immigrants are less likely to be prescribed these medications, even when controlling for demographics, doctor diagnoses, and comorbidities. Such disparities persist among individuals with diagnosed mental health conditions. Time-varying predictors, such as weather variability, do not explain the observed differentials. Findings from Chapters 2 and 3 point to systemic barriers in healthcare access for immigrants in Spain.