Illegal file-sharers will cost the European creative industries $A356bn (£215bn) by 2015, says Tera Consultants.
A report by the firm on behalf of the International Chamber of Commerce that looked at the impact of internet piracy in the UK, as well as Germany, France, Italy and Spain, also revealed that 1.2 million jobs could be lost, with 250,000 in the UK alone.
TETA Consultants said that in 2008, internet piracy caused £1.25bn worth of losses in Europe, proving it's a "major threat to the creative industries in terms of loss of employment and revenues".
"If there was ever the proof needed to demonstrate why the Digital Economy Bill is imperative for the protection of our creative industries, this report is it," said Brendan Barber, General Secretary of the Trades Union Congress (TUC), which endorsed the report.
The Digital Economy Bill sets out a number of proposals designed to tackle internet piracy, as well as ensuring all of the UK has access to 2Mbps broadband.
One of the proposals is for a 'three strikes' rule, which will see web users suspected of illegal file-sharing issued with warning letters and emails regarding their online activities. Repeat offenders could have their broadband connection slowed down or even temporarily suspended.
The bill was approved by the House of Lords this week and has now been put before MPs.
However, there are concerns that the bill will be rushed through Parliament before the General Election, without thorough consideration.