What makes people share political news on Facebook? Prior studies have identified how different features predict audiences’ likelihood to share news on social media – the so-called shareworthiness of news. However, we still know very little about the relative contributions of these different features for predicting why people decide to share news. We extend the literature by using an experimental design that can compare the relative importance of several key features that contribute to shaping citizens’ sharing decisions: a conjoint experimental design. We use an identical layout to Facebook and a probability sample of Norwegian citizens. We find that particularly content characteristics are important, and that popularity cues and message congruence is conditional on some user characteristics such as age.