Euro 6b since September 2014.
Euro 6c/d-TEMP, including WLTP and RDE step 1, starts on 1 September 2017 for new car types.
Euro 6d, with RDE step 2, will start on 1 January 2020
Current EU Legislation
Regulation (EC) No 715/2007 of the European Parliament and of the Council of 20 June 2007 on type approval of motor vehicles with respect to emissions from light passenger and commercial vehicles (Euro 5 and Euro 6) and on access to vehicle repair and maintenance information
implemented by Commission Regulation (EC) No 2017/1151 of 1 June 2017.