Abstract Health literacy, the ability to understand, access, appraise, remember and use health information and health services, has great potential to reduce health inequalities and improve access to and quality of health care, particularly among groups that experience vulnerability, including migrant groups. Across Europe, including in Portugal, little is known about the health literacy strengths, needs and preferences among migrants. We aimed to assess the health literacy of diverse migrants living in Portugal and identify if health literacy needs differ across sociodemographic subgroups. A cross-sectional survey was administered to migrants living in Portugal. Data were collected using the Health Literacy Questionnaire (HLQ), an internationally tested and robust multi-dimensional measurement tool with nine scales, and a demographic and socioeconomic questionnaire. Associations were tested using Welch's ANOVA. In total, 1126 adult migrants were surveyed: 53.4% female, mean age of 35.8 years (range 18-77), 48.9% from African countries, 29.5% from Middle East/Asian countries, 21.6% from Brazil. Low scores on most HLQ scales were clearly associated with sociodemographic characteristics such as lower levels of education: 1. Feeling understood and supported by healthcare providers (p = 0.045); 2. Having sufficient information to manage health (p < 0.001); 3. Actively managing health (p = 0.036); 4. Social support for health (p = 0.001); 5. Appraisal of health information (p < 0.001); 7. Navigating the health system (p = 0.031); 8. Finding health information (p = 0.007). Similar patterns were found for participants who were unemployed and with lower income (<650€). Health literacy needs of migrant communities should be taken into account when designing interventions aiming to mitigate health inequalities and to promote health literacy. This is even more pertinent in the current context of the COVID-19, where its adverse social and economic impacts are likely to aggravate health inequalities. Key messages Lower health literacy is related to lower socioeconomic status. Mapping health literacy needs can inform interventions to mitigate health inequalities among vulnerable migrant groups.