Units in the new Fonterra unit fund debuted on the NZX at $6.61, up $1.61, or 21%, on their listing price of $5.50.
Interest in the units, as the shares have been named by the dairy giant, was expected after the huge scaling back on applications for the units in the dairy giant.
It is the first time the investment public have had a chance to buy into the cooperative.
Fonterra priced the units at the top end of the range with 42% of the units sold off shore.
Shareholders will have dividend rights but will not be allowed to vote on Fonterra issues.
Fonterra chairman Sir Henry van der Heyden said this morning it was an historic day for the cooperative.
The fund provides a unique opportunity for the public to gain exposure to the financial performance of Fonterra and the global dairy industry.
"Farmer shareholders and unit holders will invest in the performance of Fonterra through separate structures. What they both have in common is the chance to be part of the continuing performance of our cooperative - a New Zealand success story, Sir Henry said.
Labour primary industries spokesman Damian O'Connor is warning that the launch today of Fonterra units on to the NZX will be the death knell of the cooperative as farmers know it.
Prime Minister John Key will ring a bell at noon to launch the trading.
"The Prime Minister has long been a supporter of strengthening the capital markets and providing opportunities for trading in New Zealand.
"While investors have been hugely enthusiastic about Trading Among Farmers [TAF], our famers should be extremely wary of that given the upward pressure on the share price and the additional cost that it will mean for Kiwis wanting to get into dairy."
Mr O'Connor suggested a legislative cap was needed on the number of units available for investors, something that would ensure farmers could retain control of Fonterra.
Without such protection, New Zealand's biggest and most successful cooperative wa set to become the latest victim of the Government's hands-off "she'll be right" policies, Mr O'Connor said.
