Call it nup-cycling: Instead of stashing away their wedding dresses as gorgeous, but unusable, mementoes, some happily married women are finding ways to get new life out of their (or their mother’s) old gowns.

And why not? The average cost of a wedding dress is $1,631, according to a 2018 poll by The Knot. A year earlier, the same survey found that brides in Manhattan and Long Island spend the most on the garment — $2,504 and $2,347, respectively — compared to the 2017 national average of $1,509.

But figuring out how to re-wear a white, floor-length frock is a challenge. That’s why these onetime brides came up with ingenious solutions, including a Pokemon-inspired costume and a sweet, freshly tailored dress for a flower girl.

Ahead of Columbus Day — the most popular weekend of the year to get married, per The Knot — here are five women who discovered a way to say yes to the dress yet again.

I turned my Mom’s gown into a mini

Although her mother had saved her own wedding dress for her daughter to wear down the aisle one day, Tori Sheridan had no interest in the hand-me-down gown.

“Some of my friends repurposed their mom’s ’70s dresses because the boho look came back into style,” says Sheridan, 33, who got married in June 2014. “But Mom’s was an ‘80s number with pouf-y sleeves and frills.”

Nonetheless, it fit her size-0 frame perfectly, and the realtor wanted to find some way to fit it into the celebration of her marriage to electrical engineer Ryan Sheridan.

And so — after a dry cleaner confirmed that a 35-year-old coffee stain could be removed — Sheridan decided to turn the off-white frock into a mini dress to wear to her bridal shower.

For $300, a seamstress dramatically shortened the dress and reworked the original long sleeves. “I did keep some of the pouf,” Sheridan says with a laugh. Plenty of tulle was preserved from the original to make the skirt flare out as much as possible.

The design was a hit at the bridal shower, attended by 50 guests including her mother, Vicki Carlson, 55. “It was a lot of fun,” adds Sheridan, from Glen Mills, Pennsylvania. “I felt a bit like a Barbie doll.”

Now, the mom of two hopes her daughter, Scarlett, 4, might wear the party dress when she’s older. “It’s not just any dress, it’s a tribute to her grandmother,” says Sheridan.

I channeled a classic Guns N’ Roses video

Hard-rock fan Sandy Roman knew exactly what she wanted to wear to the Guns N’ Roses-themed house party she hosted to raise money for her local library in Pelham, New York.

The mother of five has always adored the band’s melodramatic “November Rain” video from 1992, which features Stephanie Seymour marrying then real-life fiancé Axl Rose in a high-low wedding dress that shows off her supermodel legs.

So, in the weeks before the bash last November, Roman didn’t hesitate to spend $700 converting her $100 off-the-rack bridal gown into a dead ringer for Seymour’s original, $8,000 Carmela Sutera number.

“I brought my dress to David’s Bridal, and they worked magic,” recalls Roman, who wed husband, Adam, 43, a real estate executive, in August 2004.

The 41-year-old originally chose the gown for its simplicity. “I just wasn’t in the mood for [fancy] wedding-dress shenanigans,” she says of her purchase.

Fourteen years later, Roman was finally ready to strut her stuff in something over-the-top.

“The seamstress cut out the entire front of the dress and poufed it out, taking some extra material to make poufy sleeves,” she says.

Of course, the night of the party, husband Adam dressed in a $100 Axl Rose costume, complete with bandana, leather vest and kilt.

“It was a very fun evening, and everyone said we looked great,” says Roman, who spent $35,000 hosting the bash for Pelham’s Novel Night. “I’d totally wear the Stephanie Seymour dress again — probably to a Guns N’ Roses tribute concert.”

I scaled down my gown for the flower girl

Jennifer Vanderslice had carefully stored her wedding dress in a museum-quality preservation box ever since her July 1987 marriage to store manager Craig, 56.

The mother of three held onto her satin and lace gown in the hopes that her daughter Aurora, now 36, might want to wear it one day.

But alas — Aurora got engaged and made it clear that she had no interest. As wedding plans came together, Vanderslice had another thought: It might make a nice fancy frock for her 7-year-old niece, Julia Benedetto, who was recently appointed flower girl.

“I’ve always been handy with the sewing machine, and I enjoy a challenge,” says Vanderslice, 55, a literary publicist. “The bodice was beaded, so I used the material from the skirt and the train.”

It took Vanderslice just a week and a half to transform her old gown into a pint-sized confection, complete with a blue satin sash made from the hem of a bridesmaid’s dress. “Waste not, want not,” says Vanderslice with a laugh, who lives in Malvern, Pennsylvania.

Seeing her niece in her sentimental creation made Vanderslice downright weepy: “It felt meaningful to have something so precious of mine feature so prominently” at her daughter’s 2007 wedding, she adds.

Now, 12 years later, it’s getting a third moment in the spotlight as Aurora’s 8-year-old daughter, Willow, models it alongside her grandmother for The Post.

“It makes me look like a princess,” Willow says.

I lived out my Pokemon fantasy

Breezing into the Katsu Con anime convention in National Harbor, Maryland, last February, Anna Good turned heads in her tight-fitting white dress, long satin jacket and powder blue wig with a unicorn horn attached.

The 29-year-old, originally from Morgantown, West Virginia, is “really passionate about cosplay,” she says. She decided to attend Katsu Con as Dragonair from the Pokemon TV series because she admired the character’s style and resilience.

To create the look, she repurposed the $200 second-hand gown with a sweetheart neckline she wore two years earlier for her marriage to husband Anthony Hessel.

Good, an MBA graduate, hand-tailored the A-line dress to make it more form-fitting, and sewed a new electric blue jacquard jacket to go with it. She says she spent just $60 on the project, including the $35 cost of the Arda wig which she purchased on sale.

At the anime convention, her friends said she looked like a fairy princess. “I love the way the full skirt allowed me to spin around. There was a lovely flow to it.”

After the costume’s success in National Harbor, Good wore it again, to the Kikori Con event in Flagstaff, Arizona, the following month in March 2019.

“It was perfect,” she adds. “More conventions are coming up, so I might model it again. It’s great that I got so much use out of something most women wear only once.”

I still love my wedding-white bustier

Charly Rok had no intention of wearing her $1,200 wedding gown just once when she bought it ahead of her marriage in September 1999.

“I felt wonderful and magical in the dress, but it was so not my usual style,” says the 53-year-old self-described tomboy, who lives in Tribeca. “I wanted to switch things up.”

The dress was actually two pieces — a bustier and a flowing skirt — both of which she immediately repurposed. Aside from removing a few stray hooks at the waist, she’s done little to the top. Rok says she paid $100 to have the regal billowing bottom half transformed into a sassy miniskirt.

Now, 20 years later, she has lost count of the number of times she has worn the two pieces. Usually she rocks them as separates, but she made an exception and wore them together to celebrate her 10th anniversary. That night, Rok and her husband, Jason, 54, went out to dinner in Stockbridge, Massaschusetts, the town where they got married.

The lifestyle publicist says she’ll continue wearing her wedding duds. “When I put on the bustier or skirt, it takes me back to the beautiful autumn day I married Jason — my happy place.”

Stylist: Jane Ridley; Makeup: Oscar Caballero; Hair: Paulo Neto