The initial public offering of shares in the team, mired in debt after the Glazers' heavily leveraged takeover seven years ago, is expected to raise about $300 million.
Underwriters Jefferies, Credit Suisse and JP Morgan were expected to price the 16.7 million share issue at between $16 and $20 a share.
If pulled off the legendary football franchise would then be valued at $2.9 billion, far greater than any of its rivals.
The shares are expected to hit a relatively strong market on Friday, the US IPO having been delayed from July due to weakness on the exchanges.
Last year the club sought to tap into its Asian fan base with a listing in either Hong Kong or Singapore, but that effort failed to gain approval.
"We expect it to happen tomorrow," said an official at Renaissance Capital, which specializes in IPO analysis.
Home to Wayne Rooney and Rio Ferdinand, United is the most successful club in English football history and reputedly the best supported club in the world, with massive fan clubs globally, especially in Asia.
But it has struggled with the debt loaded onto the team's books since the tycoon Malcolm Glazer and his family, Miami-based investors in sports teams, took over in 2005.
Tensions over United's finances boiled over in 2010, when the club's liabilities topped one billion pounds ($1.55 billion) and fans rebelled at management, launching protests aimed at denying the club revenues.
But debts have been slashed in the past two years, and profits have grown despite the team's narrow loss of the Premier League title to cross-town rivals Manchester City this year.
Only half of the proceeds from the IPO, an expected net of $141 million at an $18 dollar price, will go towards paying down the some of the current 423 million pound debt burden.
The other half will go to the Glazers, who are contributing 8.33 million of their own "A" shares to the offering.
They will retain a lock on "B" shares which have 10 times the voting power of "A" shares, meaning their hold on the company and its finances will be barely diluted in the IPO.