Dublin is now more expensive than Central London for expats, damaging hopes that the capital could be benefit from a defection of banks and other financial institutions from the UK following the Brexit vote.
Dublin is now ranked number 16 on the list of priciest cities in Europe for expats, up from 22 last year. Central London is ranked number 17 in Europe.
The Swiss cities of Zurich, Geneva, Basel and Bern take the top four positions, in that order.
The cost of living survey was carried out by ECA International, a global software and knowledge company.
Dublin is still ranked cheaper than Paris, at number 11. The French capital is also trying to lure companies likely to flee London as a result of the June referendum that will see Britain leave the European Union by 2019.
But two other cities seen as lead contenders for an influx of jobs that might leave London - Amsterdam and Frankfurt - don't even figure on the top 20 list of most expensive European cities for expats.
The decline in the value of sterling since the Brexit vote has also seen Central London drop out of the top 100 most expensive cities in the world for expats. Last year, it was among the top 50.
"This is the first time Central London has not featured in the top 100 since ECA's Cost of Living rankings began," said Steven Kilfedder, production manager of ECA International. The surveys began in 2004.
"The weakened pound means that UK businesses are paying more when sending staff to work overseas, although it is cheaper to bring staff to the UK," he added.
"London is now cheaper than Paris, Berlin and Brussels thanks to the weak pound".
The survey analyses the price of groceries, household and electrical goods, clothing, motoring, eating out and alcohol, for instance. But it excludes rents, utility charges, car purchase costs and school fees. ECA says those costs are not included because they're often borne by the employer of an expat.
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