Marketing is used to attract both new sellers and new buyers. It is important to compare marketing expenses growth with revenue growth, since if the revenue growth lags behind then marketing is innefective.
Last reported quarter 2017 Q3 it was $23.52 million, up by 26% from $18.74 million the same quarter a year before.
Since 2015 it increased by 24%, from $66.77 million to $82.80 million in 2016.
Source: Etsy Quarterly Results.