As reported in the Irish Times on Monday, 11th June 2018, Revenue are investigating the tax affairs of several homeowners who have let rooms through the Airbnb accommodation website.
The notice issued states that it is investigating all taxes and duties, including income from providing short-term accommodation, in the years 2014, 2015 and 2016. As stated in the Irish Times article, Revenue does not specifically mention Airbnb.
If income is found to be undeclared, there are significant penalties issued by Revenue.
Read this article in full here