A comfort letter, officially an advance price agreement, is granted by national tax authorities to multinational companies, and specifies how the tax office will treat transactions between different parts of the firm.

Last October, the commission ordered Amazon to pay Luxembourg €250m in back corporate taxes because a 2003 comfort letter was unfair.

In a summary issued 8 March 2018 (PDF), the commission said that Luxembourg’s tax service received 37 advance price agreement requests in 2016. It granted 91, rejected 25 and there were 19 “applications where the taxpayer withdrew its request”.

Luxembourg tax authorities had a total of 519 arrangements (PDF) and granted 145 requests in 2015.

The commission also reported on the total number of comfort letters in force in other EU countries at the end of 2016. Across the entire bloc, tax services had 1,539 agreements with EU companies and 723 with non-EU firms.

Belgium had 655 deals with EU companies and 440 with non-EU firms.

Ireland had 5 with EU companies and 2 with non-EU firms.

The total number for Netherlands was not reported, but the commission said the country approved 221 requests to EU companies, and non to firms from outside the bloc, in 2016.