Emap's shares jumped almost 4% to 728p, as the news emerged that it was to offload the troubled division, although it would be for almost half the value it paid for the former Petersen business in 1998.
The sale, which will make Primedia the second-largest consumer publisher in the US, does not include men's magazine FHM, which is published in 15 countries.
The acquisition will add a number of complementary consumer titles to its existing titles. Motor Trend will sit next to Primedia's Automotive, while Teen Magazine will complement Seventeen.
Emap's acquisition of Petersen was pushed through by former CEO Kevin Hand in December 1998, despite wide criticism that the £720m price tag was too high. It was Hand's first major deal in his new post and it resulted in him losing his job earlier this year.
The deal went sour for Hand when the division's problems began to have a negative impact on Emap's share price. Hand was replaced by chairman Robin Miller, who will run the group until a replacement is found.
Miller said, "The impending sale of what was the old Petersen business closes a difficult and unhappy chapter in Emap's history. In the context of a difficult US market, we regard the sale as a reasonable result."
The proceeds from the sale will go some way toward paying off Emap's debt, which stands at £294m on completion of the deal. Emap took a £545m write-down on the US operation.
Primedia's share's fell 10 cents on Friday to $6.79 as news of the deal emerged.
Primedia also publishes Hot Bike, Climbing and Trucking.