One of the biggest perks of working from home is being able to wear whatever you want – besides throwing on the occasional blazer or cardigan to look presentable for a video call, no one can tell (or cares) if you're wearing your favorite sweatpants or workout gear. 

As more companies return to the office, however, people are wondering: "What should I wear?: It's a question on a lot of people's minds, as Google searches for "business casual outfits" and "casual work outfits" have both reached an all-time high in the U.S. this month. 

The answer may not be the same as before.

The Covid-19 pandemic has loosened office dress codes, Loretta Choy, the chief merchandising officer for Stitch Fix, a personal styling and shopping service, tells CNBC Make It. 

Stitch Fix has dubbed this trend "business comfort."

"It's the evolution of business casual," Choy says. It's "professional clothing that is polished but adds the layer of comfort that we've become used to after living in a global pandemic for two years."

Manufacturer Milliken & Company, for instance, announced a new, more relaxed dress code before welcoming employees back to the office at the beginning of March. 

In the past, employees were expected to dress a little more formal than business casual. The new dress code is "dress for your day," which allows associates to dress casual most days – jeans, polo shirts and athletic shoes are all approved – but more formal for client meetings or other projects that might necessitate it.

"The pandemic accelerated our efforts to modernize our policies so that our people can be successful and really enjoy their work," Craig Haydamack, Milliken & Company's chief human resource officer, says. 

If you're staring at your closet and don't know where to start with "business comfort," Choy says one of the main changes is "People are opting for stretchier, more breathable fabrics."

She recommends taking a pair of relaxed fit jeans or a comfortable dress and pairing it with a neutral sweater, or colorful accessories.

Searching the hashtags "#businesscasual" and "#workoutfits" on TikTok, Pinterest and Instagram can drum up inspiration for looks too. 

To refresh your wardrobe with a few staple pieces that you can build multiple outfits with: Choy suggests an oversized blazer, ballet flats, trousers with elastic waistbands and a knit midi dress for women, while men can wear golf pants, polos, or a pair of slim-fit jeans to the office. 

"Wearing a polo tucked into a pair of jeans is an easy way to look pulled together and stylish," Choy says. 

Sneakers are acceptable, too, as long as they're clean and made out of material that's similar to dress shoes, like leather or suede. 

The goal, Choy says, should be to have a work wardrobe that's "polished, comfortable and versatile" – and when in doubt, you can always ask your manager if there are guidelines you should keep in mind, or text a co-worker. 

Check out:

50% of companies want workers back in office 5 days a week–why experts say this strategy could fail

Experts share the No. 1 pandemic work trend they think will stick around

How people have changed the way they think about work, according to their therapists

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