Are the rich more selfish than the poor? One often finds claims in the popular press, literature, music and the Bible suggesting many people believe this to be the case. Up to date, the literature has found some evidence that points to this belief, but most of this evidence comes from laboratory experiments. We conduct a natural field experiment on ethical behavior between upper class and lower class citizens in a medium sized city in the Netherlands. A transparent envelope is misdelivered and we measure if the card is returned to the intended recipient. We distinguish four treatments. Two treatments contain cash, either 5 euro or 20 euro, that is clearly visible. Two additional treatments contain bank transfer cards, for the amount of 5 euro or 20 euro. These latter two treatments give a measure of the opportunity costs of time for upper and lower class citizens. The results show striking differences between the two social classes. Additional evidence is gathered to understand the differences in behaviour.