Sampling of migrants in cross-national survey research is challenging. Established techniques such as random-route sampling or random-digit-dialing are associated with high monetary costs, in particular when small migrant groups are targeted. The use of onomastic (name based) telephone sampling is a relatively cost-efficient alternative, but it relies on a number of conditions (e.g., existence of telephone directories in the respective countries and inclusion of the target population). As the use of social networking sites (SNSs) has spread around the globe in the last 20 years, the present paper investigates whether a specific SNS, Facebook, can be used to sample migrants, with the ultimate goal to supplement other approaches. This article is based on data collected as part of a survey that used Facebook advertisements to sample Polish migrants in Austria, Ireland, Switzerland, and the United Kingdom. The study succeeded in sampling a total of 1,103 individuals who completed the relatively extensive questionnaire within the field period of 8 weeks (1,100 within the 4 weeks the advertisements were placed). In contrast to most of the few other studies that tried to sample respondents with the help of Facebook advertisements, no incentives were used. With nearly all (96%) of the respondents belonging to the target population and a total sampling budget of 500 (US$557), the method can be considered both accurate and cost efficient in recruiting people from the target population. Furthermore, our results suggest that the vast majority of the sample would not have been reached if onomastic sampling had been employed.