Step into some start-up offices these days and you might think you’ve wandered into a house party.

The “no shoes” office is no longer a novelty, The New York Times reports.

A growing number of start-ups — particularly in tech and artificial intelligence — are asking workers and visitors to leave their footwear at the door, blurring the line between home and workplace.

The trend has spread quietly but steadily. The website noshoes.fun, created by Ben Lang, an employee at the start-up Cursor, lists more than a dozen companies with shoes-off policies, including A.I. firms like Replo and Composite.

“I’ve only worked at startups that have a no-shoes-in-office policy,” Lang wrote on social media last summer.

At Spur, a Manhattan-based start-up that uses A.I. to scan websites for bugs, employees change into branded slides when they arrive. Guests are asked to do the same.

“It makes it feel like a second home,” said Sneha Sivakumar, Spur’s co-founder and chief executive, who leads a team of about 10 employees. “It disarms you in a positive way.”

Sivakumar said the practice also reflects her upbringing. Growing up in an Indian family in Singapore, removing shoes in homes and temples was a sign of respect. Keeping street dirt out of the office, she added, is an added bonus.

Workplace experts say the trend reflects deeper cultural shifts accelerated by the pandemic.

Nick Bloom, a Stanford economist who studies work culture, called it an extension of the “pajama economy” — the lingering influence of work-from-home habits now creeping back into offices.

“People got used to being comfortable at home,” Bloom said. “Now they’re bringing those expectations back with them.”

The practice also fits with the long hours common in Silicon Valley and start-up culture. In an environment where employees may spend 10 to 12 hours a day at work, Bloom said, “you might as well wear your slippers in the office if you’re not getting to wear them at home.”

Casual dress codes are nothing new in tech. Programmers have long favored hoodies and sneakers over suits. But shoes have come and gone as companies mature.

Notion, the productivity software company founded in 2016, once banned shoes but later reversed course.

Stripe, founded in 2010, was “shoes optional” until 2019.

Gusto, the payroll and human-resources company, began in a Palo Alto house in 2011, where changing into slippers was an early ritual. Today, most employees keep their shoes on.

The shoeless office has even made appearances in pop culture. In Mad Men, Don Draper’s eccentric boss famously padded around his Manhattan agency in sock feet, urging others to do the same.

Still, the trend is unlikely to sweep corporate America.

But at least for now, the shoeless office remains a marker of start-up identity — informal, youthful and intentionally homey. Just don’t forget your socks.