Historically, the Netherlands has hosted a large number of migrant sex workers. Since sex work is considered a legal profession it might serve as an example of better access to health services, including HIV testing, at least for those working within the legal framework. However, migrant sex workers, especially non-European Union (EU) nationals, might not be eligible to register for official employment and thus face obstacles in obtaining access to health services, becoming essentially invisible. This study examined context-specific vulnerabilities of migrant female sex workers (FSWs) from Belarus, Moldova, Russia and Ukraine, whether and how they have access to HIV testing compared to other EE, non-EU migrant FSWs in Amsterdam in the Netherlands. We conducted a multi-stakeholder perspective study from November 2015 to September 2017 in Amsterdam. The study comprised 1) semi-structured interviews with key stakeholders (N = 19); 2) in-depth interviews with Eastern European, non-EU migrant FSWs (N = 5) and field observations of the escort agency working with them; and 3) in-depth interviews with key stakeholders (N = 12). We found six key barriers to HIV testing: 1) migration and sex-work policies; 2) stigma, including self-stigmatization; 3) lack of trust in healthcare providers or social workers; 4) low levels of Dutch or English languages; 5) negative experience in accessing healthcare services in the home country; and 6) low perceived risk and HIV-related knowledge. Having a family and children, social support and working at the licensed sex-work venues might facilitate HIV testing. However, Internet-based sex workers remain invisible in the sex-work industry. Our findings indicate the importance of addressing women's diverse experiences, shaped by intrapersonal, interpersonal, community, network and policy-level factors, with stigma being at the core. We call for the scaling up of outreach interventions focusing on FSWs and, in particular, migrant FSWs working online.