Best Buy has a major cost-cutting operation in the works, and the code word is “pink slip.”

The nation’s biggest electronics chain — which saw sales fall 2.6 percent during the Christmas selling season because of a price war with Amazon — has begun laying off thousands of midlevel managers nationwide as it girds for even more competition, The Post has learned.

After slashing hundreds of jobs at Best Buy’s Minneapolis HQ last year and closing unprofitable stores, CEO Hubert Joly is now swinging the ax across the retailer’s 1,056 US big-box stores and regional offices, according to insiders briefed on the plans.

No store closings are planned in this latest round of cuts, and the exact number of pink slips hasn’t yet been confirmed. But one insider said layoffs could affect upward of 2,000 managers and supervisors.

“This is ripping off the Band-Aid,” one Minneapolis source told The Post, noting that Joly is making the layoffs in a hurry to avoid uncertainty and prolonged pain.

Indeed, about 500 field managers were notified of the cuts last week, while store-level management is expected to get the news by next week, said one source.

A spokesman for Best Buy, which is slated to report results Thursday, declined to comment.

Joly, a former restaurant-and-hotel exec who took the reins in August 2012, is resorting to the ax after recent rounds of cutbacks on contracts with outside vendors and worker benefits.

Last week, in an internal memo to employees reviewed by The Post, Joly signaled “field leadership changes” designed to reduce head count in a “thoughtful, purposeful way.”

Most of the affected workers are from the middle management ranks, many of them commanding salaries that soar into the six-figure range as they supervised product categories at more than a dozen stores each.

The idea, Joly told employees in last week’s memo, is to give the manager of each store location the “full ability to run their (respective) stores.”

On the flip side, however, remaining managers in the field will be spread increasingly thin, in some cases forced to supervise two to three times as many locations, insiders said.

The bloodbath at regional offices is intended to minimize the carnage inside stores, as Joly looks to trim costs without compromising Best Buy’s customer service, according to sources.

As such, the firings aren’t expected to affect employees that directly assist shoppers. Still, it’s likely that some will see their hours cut, one source said.

The prospect of fresh firings rose for Best Buy employees last month after the company reported squeezed holiday margins, worsened by deep discounting and dwindling demand for cellphones.

The Jan. 16 announcement sent the retailer’s stock tumbling 35 percent. Two weeks later, Best Buy disclosed it is laying off 950 workers in Canada, or 6 percent of the workforce there.

Best Buy shares rose 2 percent on Wednesday to $25.82, plus another 1.4 percent after hours.