Behavioural economics is a relatively new field of economics which studies the effect that peoples’ behavior has on their decisions. Experimental economists, unlike traditional economics, have showed that people are not always self-interest and in many occasions tend to be pro-social. This thesis is about the effect that peoples’ wealth can have on their pro-social behavior and more specifically on their willingness to donate money to those who are in need. To my knowledge, there is not much research available in this domain and the offered studies are based on existing data and subjective wealth indicators. Nevertheless, in this paper a natural field experiment has been conducted in order to investigate this relation. The findings showed that wealthy people donate more money to charity than those with a low income and also provided evidence that both low and high income people give to philanthropy with the same frequency. This study can be valuable in several domains such as the governments which can become aware of which social class is more prone to tax evasion and to humanitarian charitable organizations since they can locate the best target group.