Clouds play a key role in weather and climate. Pure liquid water droplets are liquid until about −35 °C without the presence of a small subset of aerosols, ice-nucleating particles (INPs). These INPs lead to primary ice formation and therefore impact the phase of clouds. The dataset described herein provides INP concentration measurements at two altitudes. Connecting this data to synoptic conditions and ambient data might provide a better understanding of INPs in Finnish Lapland.