The Red Devils are the most lucrative sports franchise in the world according to the valuation but they will still be raising less than they initially had hoped for
Co-chairmen Avram and Joel Glazer, along with chief executive David Gill, were smiling and applauding as United representatives were given the honour of ringing the opening bell at the New York Stock Exchange before trading began at around 14:30BST.
The listing sees around 16.7 million shares – the equivalent of 10 per cent of Manchester United - up for grabs on the US market.
The selling price for each share has been set at around £9 ($14.05), which gives the club an overall value of £1.5 billion ($2.32bn) and makes the Red Devils the most valuable sports franchise in the world.
That status puts them above Real Madrid, baseball giants the New York Yankees and NFL stalwarts the Dallas Cowboys.
However, the club had hoped to float the shares at a much higher price - between $16 and $20 dollars (£10-12). That would have been worth around £2.1bn to the club.
The lower flotation price comes as a blow to the Glazer family, who had previously failed to garner sufficient support in a bid to also sell shares on stock exchanges in Hong Kong and Singapore.
The Glazers bought the club for £800m in 2005, meaning it has almost doubled in value since that purchase.
The flotation on the stock exchange is expected to raise around $233m (£150m) in profit for the club after the running costs of the operation have been deducted.
Some of that money will go towards paying off some of the club's £437m debt but the rest will go directly to the Glazers, which has angered the club's supporters' groups.
Despite the start price of the shares being discounted, the initial growth was steady at less than 5%.