Welcome to the jingle cells!

A festive Bronx precinct boss turned the drab old pens in his stationhouse into the borough’s answer to the Saks Fifth Avenue windows — using lights, tinsel, elves and other decor to spread holiday cheer.

“The whole purpose is to bring the community to our house,” commanding officer Deputy Inspector Ernest Morales III told The Post.

“Instead of ‘Miracle on 34th Street,’ this is our Miracle at the 42nd Precinct.”

The displays are inside jail cells, but you don’t have to be on the NYPD’s naughty list to check them out — cops will soon open the festive exhibit to the public as an ice-breaker.

It’s a first for the stationhouse, which has previously reimagined itself as a Halloween haunted house. The 14 cells haven’t held prisoners since the 1990s, and their transformation from dank and dingy closets to bright and festive dioramas is nothing short of miraculous.

Wrapping paper covers their sickly metal bars and graffiti-scarred walls, while Christmas lights, garland and stuffed toy elves lend an air of whimsy to the once-dour dungeon.

One room is tricked out to look like Santa’s office, with a naughty-and-nice list, ersatz fireplace, cup of cocoa and even a nameplate reading “Mr. Claus.”

Another is an homage to Hannukah, while a third is dedicated to the Grinch — who is apparently cooling his heels on “grand theft holiday” charges.

Others cells are decorated after Disney’s “Frozen,” the Bronx elevated subways and, naturally, a Nativity scene.

Morales was inspired by the holiday windows he saw along Fifth Avenue as a kid.

“I remember growing up and going to see these displays and loving them,” he said. “It left an indelible impression on me, so that years later — when I’m able to — I brought it here to the 42nd Precinct.”

“He wanted to bring Macy’s to the Bronx,” said Police Officer Erica Bukowiecki, who wrangled the project.

Bukowiecki got fellow cops and local community members to “adopt” and decorate the cells in their off time over the last eight weeks. The precinct kicked in $3,000 and volunteers — such as a 99-cent store that donated decorations — spent thousands more on the effort.

“I’m looking forward to seeing all these children and their families coming through,” Bukowiecki said. “I want to hear their ‘oohs’ and their ‘aahs’ and [see] how their eyes look.”

She’s in for a treat, because kids who got a sneak peak were blown away.

“I can’t tell that’s a police station. It’s fancy. I want to see it all,” raved local 10-year-old Joshua Hunter when The Post showed him a photo of the cells.

Cops will give tours on afternoons from Dec. 17 to 22, when Santa will stop by the precinct to hand out gifts to kids under 12, Morales said.

The command’s actual inmates are housed in another area, so they won’t get to share in the festivities — and visitors certainly won’t have to walk by them to get to catch a glimpse of the converted cells.