(Katherine Frey/The Washington Post; Prop styling by Clare Ramirez/The Washington Post)

For their November wedding, Ann Marie Amick and Michael Martin spent hours fine-tuning their registry. They requested steak knives and serving bowls, picture frames and pitchers.

And then, after some soul-searching, they added this: tickets to Harry Potter World.

“You get engaged and you’re like, ‘What do I do? What’s proper and what isn’t?'” said Amick, 31, a photographer in Brooklyn. “I literally Googled, ‘Is it in poor taste to ask for TSA pre-check?’" (Answer: No. She added it to her registry.)

The rules of wedding registries are changing. It’s been nearly a century since Marshall Field’s, the now-defunct department store chain, popularized the idea of buying preselected wedding gifts. For decades, Americans dutifully asked for — and bought — housewares, china, bedding and other household staples from retailers’ registries.

But today, 15 percent of 25- to 34-year-olds live together without marriage, up from 12 percent a decade ago, according to the census. That means they have less need for new towels, duvets or baking pans when they get married. Instead, they are registering for, among other things, honeymoons, home down payments and wedding expenses. Also on their wish lists: Funding for fertility treatments, help paying off student loans and, in some cases, contributions to their future children’s college funds.

Amick and Martin have been living together for almost three years, so after some requisite kitchen and bedding items, they quickly ran out of gifts they needed, or wanted, for their Brooklyn apartment. Although neither had planned to ask for cash, they ended up padding their registry with requests for round-trip tickets to the Philippines, Jet Ski rentals and a snorkeling adventure for two.

“Our home is pretty put together,” Amick said. “If we don’t get new bedding, it’s not the end of the world.”

Retailers, restaurants and start-ups are taking note. A single wedding registry can bring in tens of thousands of dollars in sales, and companies are increasingly thinking beyond kitchen gadgets and housewares in courting couples. Domino’s Pizza, REI and Walmart all offer wedding registries, as does Home Depot.

“The trends really reflect the demographic of people who are getting married today, which is millennials,” said Jennifer Spector, brand director for Zola, a wedding registry site that allows couples to ask for cash and experiences. “Couples are living together beforehand, they’re older and have more refined taste.”

That’s not to say brides and grooms are forgoing housewares all together. When they do ask for traditional gifts, they tend to be higher-ticket “upgrade” items, Spector said.

“The number-one gift on Zola is — and always will be — the KitchenAid mixer,” she said. “Number two? A $100 Airbnb gift card.”

Other popular items on the site include gift cards for Uber and SoulCycle, as well as airlines and travel sites.

At Domino’s Pizza, registry orders bring in millions of dollars of business each year. The company introduced the service two years ago as a “fun and surprising way” to reach its most loyal customers, spokeswoman Jenny Fouracre-Petko said. Since then, invitees have purchased more than 150,000 gifts, including the company’s most popular option, a “post-honeymoon adjustment to real life” package for $25.

The Domino’s registry came in handy for Tara and Nick Logothetis, who got married in December. The couple also created an Amazon registry, where they asked for more traditional items including a Kitchen-Aid mixer, as a well as a third registry for honeymoon funds. But after some thought, Tara Logothetis said she decided three registries was “overkill.” One had to go.

“When it came down to it, pizza won over the honeymoon fund,” said Tara, 31, a dental hygienist in Pennington, N.J. “Everyone thought it was very ‘us.'" And they enjoyed pizzas with tomatoes, onions and hot sauce — delivered to their hotel room during their honeymoon in Sedona, Ariz.

Tori Pelham and Shaun Durkan’s wedding registry, meanwhile, includes $1,200 worth of Airbnb gift cards — enough, they said, to fund six weekend getaways to Napa Valley or the beach. The couple, who are moving to San Francisco from Brooklyn later this year, have been living together for four years. They are also asking for contributions for a house down payment, a honeymoon in Greece and a service that will handle Pelham’s last-name change (valued at $69).

“My parents’ generation, my grandparents’ generation, they really want to buy you the sheets or the vacuum cleaner,” said Pelham, a 31-year-old interior designer. “But people our age, they understand that we’ve got a lot of stuff. Getting more stuff is meaningless.”

Although, there is some stuff she would like: The registry also includes confetti-patterned serving bowls, banana-print bedsheets and a gnome-shaped stool.

“Things that make life fun,” she said. “We still want some tradition."

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