BNC and PMK/HBH have made it official: They will merge operations at the start of next year to form Hollywood’s biggest PR shop.

The companies announced Tuesday that the merged entity will be dubbed PMK-BNC, with offices in West Hollywood and New York. The 150 employees at the companies — both owned by advertising/marketing giant InterPublic — first received word of the merger on Dec. 7.

With BNC’s strength in corporate clients and PMK/HBH’s in high-profile stars, the combo has impressed outsiders as making strategic sense. Execs with both shops stressed the complementary nature of the operations and said no layoffs are contemplated.

“We’re going to be very hands on,” said current PMK/HBH co-CEO Cindi Berger, who started as the receptionist at PMK more than 20 years ago.

Both are located at the Pacific Design Center in West Hollywood, one floor apart. The new PMK-HBH will have about two thirds of its staff on the West Coast and the rest in New York.

BNC chairman-CEO Michael Nyman will hold the title of chairman-CEO and oversee the company. Berger will also hold the posts of chairman and CEO and focus on the entertainment and media relations portion of the business.

BNC prexy-chief operating officer Chris Robichaud will also have the title of CEO and will be responsible for operations and the consumer brand marketing and PR portion of the biz. BNC co-founder Brad Cafarelli will be vice chairman.

Nyman told Daily Variety that the move makes particular sense at a time of massive change in entertainment and consumer marketing. “Individual clients and companies are looking for a new way of doing business,” he added.

Several vets said the traditional PR biz model — charging a retainer of $5,000-$10,000 a month — has become increasingly difficult to sustain from a profitability standpoint, particularly for rising stars.

The merger’s already created fallout with the HBH components of PMK/HBH departing. Chief exec Simon Halls announced plans to leave a week ago, and managing partners Robin Baum and Stephen Huvane ankled along with execs Andy Gelb and Shawn Purdy to join up with PR vet Ina Treciokas. In addition, PMK/HBH execs Melissa Kates and Jennifer Allen are forming their own operation, and PMK/HBH prexy Nate Schreiber departed two weeks ago.