The original downtown label Lafayette 148 is also living in an uptown world. The fashion house has opened a gleaming new boutique at 956 Madison Ave., across from the Met Breuer on one of the city’s swankiest shopping streets.

“Lafayette 148 has always been a New York brand with a New York story,” says CEO and co-founder Deirdre Quinn, who launched the brand in 1996 (at its namesake Soho address) with fashion veterans Shun Yen Siu and Ida Siu. “It’s the right neighborhood, the right location and the right feeling for us. It all came together.”

The Townhouse, as it is called, marks the third NYC flagship for the brand — and perhaps its most sumptuous. The entrance of the landmarked building is double-height with floor-to-ceiling windows, so the elegant space is flooded with natural light and feels like home.

“We were able to mix leathers with woods and metals and touches of onyx stone, to make it inviting and create unique accents,” Quinn tells Alexa. “There’s almost a library effect to it, with items like heirloom glass throughout the store, luxurious dressing rooms and a guest bar,” she says, noting that customers can enjoy Champagne and light refreshments while they browse.

The amenity level is just as extra as the aesthetic. Personal stylists are available for private shopping sessions in the second-floor salon; on-site tailoring is complimentary; and same-day white-glove delivery is free in the five boroughs.

What’s more, if a customer wants to order a special size, the Upper East Side flagship can usually make it happen.

“If we have the fabric and the pattern in Brooklyn, where our headquarters is, we will turn it around in 48 hours. That’s pretty ‘wow,’” Quinn says. “We’re known for our ability to give the customer incredible service.”

In addition to the ready-to-wear, accessories and shoe collections, the outpost will also carry a store-exclusive “Made for Madison” capsule. The first drop includes glamorous evening pieces and hand-crocheted knits. “We wanted the store to have the best of the best,” Quinn says.

This season, standout collection pieces include a hand-painted snake-print leather trenchcoat, a cashmere funnel-collar cable sweater or a lacquered lambskin skirt. “When the customer can touch and feel the product in person, she sees the unmatched quality of the cashmere, the precision of all the hand-finishing,” she observes. “We establish a bond with the customer and it’s an experience.”

The brand is celebrating its new digs and fall campaign, #WeAreNewYork, with a photography exhibit by famed lensman Patrick McMullan. Called “Glamour, Grit & Grace: Portraits of Iconic New York Women,” it features 28 black-and-white portraits of luminaries such as Debbie Harry, Sarah Jessica Parker, Fran Lebowitz and Liza Minnelli. They will be on display from Oct. 24 through December.

“We’re a women-led company,” Quinn says. “Some of those iconic women wear Lafayette 148 already, so it makes you smile when you see these pictures.”