Zurich and Geneva are ranked as the first and second most expensive expat cities in Europe and the 5th and 6th most expensive cities for expatriates. This is due primarily to the strong Swiss Franc which has maintained its position against the US Dollar despite the dollar’s strong showing in 2015, as well as due to high rentals and institutionalized high wages.
An interesting observation is that only one of the top ten most expensive cities in Europe is on the Euro (Monaco).
Oslo is the world’s 7th and Europe’s third most expensive city as at July 2016. Oslo was the most expensive location in Europe in 2014, however the weaker Norwegian Krone resulting primarily from the lower global oil price and subsequent weaker oil sector, contributed to Oslo becoming relatively cheaper in global terms during 2015.
Bucharest in Romania is the cheapest city for expatriates in Europe. Bucharest is particularly cheap for communication, groceries, healthcare, and housing.
http://www.xpatulator.com/cost-of-living-article/Europe-Expat-Cost-of-Living-Comparison-Rankings-July-2016_684.cfm