The paper aims to examine factors influencing the regional distribution of companies with foreign capital in Poland. The author uses a negative binomial model based on data covering the country’s 16 regions/provinces in 1990-2004. The study expands previous empirical analyses based on data for Poland’s 49 former provinces. The author checks if companies with foreign capital take into account the same factors while making their siting and investment decisions. It turns out that the latest data applying to the 16 regions is less distinct than that obtained in the past with regard to the former 49 provinces. This is due to a high level of data aggregation in the country’s new administrative division, the author explains. The 16 new provinces are larger than the old provinces, as a result of which differences between them are less considerable than in the case of the former provinces. Still, some trends are independent of the degree of data aggregation. These include a positive relationship between the number of companies with foreign capital operating in a given region and the share of the service sector in the overall labor force. Another rule is a negative relationship between the number of companies with foreign capital and real wages and unemployment in the region. The border location of individual regions produces less distinct effects for today’s 16 provinces than in the case of the former 49 provinces. The feedback effect that was found in earlier studies involving the 49 former provinces does not occur in the current regional arrangement based on 16 provinces. Indicators describing the influence of special economic zones on regional economies are statistically significant only when the relevant regression equation takes into account the effects of a region’s border location.