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 2019 Q2 it was $45.99 million, up by 59% year-over-year from $28.94 million. From $109.09 million in 2017 it increased by 45% to $158.01 million in 2018.
Source: Etsy Quarterly Results.