Following its accession to the EU and the progressing relaxation of the legislation on employment of foreign workers, Poland started to attract more and more job seekers from other countries, mainly from Ukraine, who saw opportunities in its expanding labour market, increasing demand for workers, falling unemployment and rising wages. The inflow of workers from countries east of Poland has benefitted its economy in many ways, including the narrowing of the demographic gap and increased funding for the national budget and the Social Insurance Institution (ZUS). This study was undertaken to determine the types of factors causing Ukrainian and Belarusian nationals seeking employment in Poland to prefer one Polish county over the others and to assess their role. Based on the review of studies on the key determinants of migration, and given the limited availability of data, three major groups of factors that can be associated with their choices were selected for analysis – the distance between the migrant’s home and Polish counties, their socioeconomic status, and the presence of migration diasporas. The analysis was performed by means of the widely used gravity models that describe population movements as a function of a geographical distance, and a taxonomic measure of counties’ socio-economic development. The main sources of data used in the article were Statistics Poland (www.stat.gov.pl) and Ministry of Family and Social Policy (https://psz.praca.gov.pl/web/urzad-pracy) and Educational Information System (https://dane.gov.pl/pl/dataset/1426,liczba-uczniow-cudzoziemcow-wedug-gmin/).