A majority of 72 percent of respondents believed financial centre Frankfurt, rather than rivals Dublin, Paris, or Amsterdam, would gain the most from Britain leaving the European Union, the study of 555 firms by consultants Ernst & Young (EY) found.
The German property market as a whole would get a boost from Brexit, 57 percent of those polled said, with large majorities expecting prices for commercial and residential properties to increase.
Brexit could be a further push to Germany's once sleepy market, which in recent years has seen prices begin to rise more steeply.
"It looks like international investors who for now don't want to invest any more in London will flock to the German property market even more," EY real estate expert Christian Schulz-Wulkow said in a statement.
Britain's June 23 vote to quit the EU has afflicted the powerful London financial sector with uncertainty.
With possibly years to wait until rules governing how UK businesses can trade with the EU are thrashed out, some are already looking to relocate activities that could be affected to cities inside the remaining 27 member countries.
Centrally-located Frankfurt is seen as having an advantage over European competitors jostling for business fleeing London, as it already hosts the European Central Bank and many private-sector banks.
Meanwhile, 14 percent of firms said they were already planning to reduce activities in the UK.
That was far short of the 33 percent of companies who said they would maintain their UK operations at present levels.
But "for a large proportion of the respondents, the future direction of their business still seems to be unforeseeable," Schulz-Wulkow said.
A majority of 55 percent said the outlook was too uncertain to say how the Brexit vote would affect their UK business.
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