Australia was first in line on Friday for a financial hammering now rolling across global markets as investors ponder the economic fallout of Britain leaving the European Union.
Markets across Asia, the UK, Europe and the US are set to mimic heavy losses across in Australia after a surprise victory for the Brexit vote.
Britain's departure from the EU after 43 years raises uncertainty that investors don't like, Patersons Securities economist Tony Farnham said.
"There's quite a few unknowns: what will the UK Parliament think of this, will they try and reverse it in some way," Mr Farnham said.
The biggest stock market falls are expected in the UK and Germany, the two biggest members of the EU.
The UK's FTSE 100 index was down about seven per cent soon after trading began on Friday, the day after the historic vote on Thursday UK time.
Germany's DAX was 8.1 per cent lower.
Wall Street is also set for big losses, with the S&P 500 futures down 3.9 and Nasdaq 100 futures pointing to a fall of four per cent.
Australia was always going to be a "forward scalp" as the stock market was trading as the referendum votes started to filter through, Mr Farnham said.
"The bottom line is we're the ones that are trading at this time so we get to be the first opportunity for markets to react, for global investors to react," Mr Farnham said.
"And then we focus on the true picture tonight when European and US markets fire up because by then the result will be signed off on."
The Australian share market dropped more than three per cent, wiping out $56 billion in value. It was the biggest one-day fall in nine months.
In Asian markets, Japan's Nikkei 225 index was down nearly eight per cent in Friday trading, with Hong Kong's Hang Seng dropping 4.4 per cent and Singapore's Straits Times index slipping two per cent. The UK voted by 51.9 per cent to 48.1 per cent to leave the EU in a historic referendum, according to the BBC's website.
The outcome is a surprise given recent polls ahead of Thursday's referendum pointed to a stay victory.
The Australian dollar plunged against the US dollar and collapsed against the Japanese yen as investors flocked to the safe-haven assets.
The currency tumbled from a two-month high of 76.35 US cents earlier on Friday to just 73.29 cents by 1600 AEST, it also sank from 81.20 Japanese yen to 74.31 yen.
However, the Aussie has soared against the pound, to 54.64 pence, as the UK currency suffers its biggest single-day drop since Black Wednesday in September, 1992, falling its lowest level in 31 years.
"Today's market moves are in part about thin liquidity in currency markets and about markets getting it wrong by removing risk premium in the run up to the event," CMC Markets chief market strategist Ric Spooner said.
Meanwhile, the bond markets were on fire as edgy investors panic-bought safe-haven assets.
Both corporate and government bonds yields were hovering around all-time lows of just 2.0 per cent at 1600 AEST.
