Best Buy Co. Inc. will stop using a single agency as its main advertising partner, the company said Tuesday, and will instead hire agencies on a project basis and do more work on its own.

The move is aimed at saving costs and drawing on a broader base of marketing talent for ideas. "It's certainly a way to tap more creativity," Best Buy spokesman Jeff Shelman said.

It's the biggest strategic decision yet by new leaders in the marketing team at the Richfield-based electronics retailer. Greg Revelle, a former top marketer at AutoNation Inc. and Expedia Inc., became chief marketing officer last November. The company's former marketing and advertising chiefs subsequently left and Revelle has been building a new team.

The change, first reported by AdWeek, upends Best Buy's close relationship with Crispin Porter + Bogusky, the Boulder, Colo.-based firm that has been its agency of record since 2008.

Shelman praised the firm, known as CP+B, and said Best Buy hopes to continue working with it on future projects. "They've been a great partner of ours," Shelman said.

A representative of CP+B did not respond to a request for comment.

With the move, Best Buy joins a growing number of large companies that have shed the traditional agency-of-record way of doing business with outside marketing experts. The model, which emerged after World War II and was visible on TV shows like "Bewitched," "thirtysomething" and "Mad Men," is giving way because of pressures to decentralize and lower costs created by social media, the Internet and digital ­production.

Instead of relying on a single agency to create an ­all-encompassing campaign, advertisers are seeking smaller projects that cost less to make and can be distributed quickly on Internet sites, mobile social media platforms like Vine and Instagram, as well as traditional media. In turn, advertising agencies are making changes to their staffing levels and structures.

CP+B has already developed Best Buy's advertising for the summer and back-to-school seasons. With the change now, Best Buy has plenty of time to seek help from other agencies for the year-end holiday season, the biggest sales time of the year for it and most retailers.

CP+B helped Best Buy develop memorable ads for the holidays in recent years and for the Super Bowl in 2011, 2012 and 2013.

In 2011, they created a commercial that co-starred Ozzy Osborne and Justin Bieber to promote Best Buy's program to buyback used electronics goods. The spot ended with Osborne expressing bewilderment at the upstart new star with the line, "What's a Bieber?"

For the holidays in 2013, the agency lined up several celebrities to read storybook tales that aligned with new products in Best Buy stores. Just as often, however, it created ads that used real Best Buy employees.

Evan Ramstad • 612-673-4241