TransferWise could move its London headquarters to the continent after Britain voted to Brexit.
The foreign exchange service is among several major firms putting expansion plans on hold in the UK following the outcome of Thursday’s EU referendum.
Its chief executive and co-founder Taavet Hinrikus said: “It’s unlikely we will close our London office.
“But we will probably not grow the team based here much more.
“Headquartering elsewhere is a possibility but we haven’t made a final decision yet.”
The tech sector was extremely supportive of remaining in the EU, according to polls in the run-up to the vote, while hundreds of tech start-ups and entrepreneurs signed an open letter opposing Brexit in April.
Concerns include loss of access to qualified workers from overseas to counteract the skills gap and a loss of access to the Digital Single Market.
“This is likely to affect regulation and the movement of talent, two massive issues for business,” added Hinrikus.
“The two main benefits of being part of the EU are access to talent because of the free movement of labour and the fact that you can ‘passport’ regulation so if you’re regulated in the UK, you’re regulated across the EU.
“We don’t know what’s going to happen with either of those.”
There are fears that the Fintech sector in particular will be hit hard as access to European markets is lost despite London’s previous status as the financial capital of Europe.