Investors in Viking Global Investors will soon be getting an $8 billion refund as one of the hedge fund’s top stock pickers prepares to leave this month.

The $32 billion hedge fund, run by Norwegian-born Andreas Halvorsen said in a letter to investors Monday that it will be returning $8 billion to investors amid the exit of chief investment officer Daniel Sundheim.

Sundheim, 40, “is in a league of his own as a stock picker and portfolio manager,” Halvorsen said in the letter, which was first reported by Bloomberg.

The fund has already sold down its holdings to allow for the return of some of the $8 billion in August. The downsized asset base is expected to give the fund more of a runway for growth, a source close to the matter told The Post.

According to a January letter sent to investors, Sundheim had been directly overseeing more than half of the fund’s capital, instead of the typical 25 to 40 percent.

As Viking reported losses of 4 percent for 2016, Halvorsen then called Sundheim’s excess an “unsustainable load to carry.” Soon thereafter, Sundheim’s direct reports were reduced from six to three.

Nevertheless, Halvorsen said Monday that he “looks forward to opportunities for collaboration” with Sundheim. Meanwhile, portfolio managers Ben Jacobs and Ning Jin will be stepping up to replace Sundheim as co-chief investment officers.

Sundheim, whose exit was called “amicable” by a source, had been with Viking for 15 years. The letter said that Sundheim is pursuing “entrepreneurial” endeavors and was hoping for more flexibility in managing a portfolio.

Halvorsen founded Viking Global in 1999, following his exit from Julian Robertson’s Tiger Management. Viking is one of several hedge funds known as a “Tiger Cub” — a moniker for funds launched by Robertson’s proteges. Other cubs include Blue Ridge Capital, Lone Pine Capital and Coatue Management.