Protesters in black armbands are handing death notices for 12 European currencies to people heading to work in the City of London.
Demonstrations are taking place until the end of the morning rush hour at Liverpool Street and Fenchurch Street stations and other locations.
A public rally is also planned outside the Bank of England at 12.30pm.
Protest organiser Jim Reynolds, a member of the national committee of the cross-party Campaign for an Independent Britain, says: "We simply could not let this momentous day pass unremarked.
"We want people to understand the full significance of scrapping your currency, one of the most potent symbols of nationhood, and handing over economic control to unelected banking officials in Frankfurt.
"The euro 12 have not only sacrificed their independence, but also a large part of their nationhood.
"It is a dark day for democracy in Europe and it is crucial that Britain should not fall into the same trap," Mr Reynolds adds.