Stylists and designers share 7 items that will always be business casual and 6 that absolutely aren't

Trousers — for any gender — are always appropriate for work, according to Monica Diaz, personal stylist and owner of Monica Diaz Mode.

"These can be in wool for winter and cotton in warmer weather," she told BI.

A polo is clean-cut and nice without being overcomplicated, according to Melony Huber, founder and design director of La Peony.

"A polo can take you straight from the meeting room to the networking event or out to dinner or golf," the designer told BI.

She said it's a versatile top that should be on everyone's list when packing for a business-casual work event.

Chino pants are a great midway point between casual and formal, according to Patrick Kenger, personal and celebrity stylist and image consultant at Pivot.

Diaz also touted the simple pants and said they should fit well (not too oversized) and be neutral in color (black, blue, brown, or tan).

According to Kenger, tailored dresses are widely considered to be an appropriate choice for business-casual environments.

"It's a good idea to opt for styles that are not too tight or revealing, and perhaps consider pairing it with a blazer or cardigan for some added warmth and polish," he told BI.

Footwear can seem especially challenging when it comes to putting together a business-casual look, but Kenger said loafers are a fairly safe bet.

Opt for leather or suede options in neutral colors.

A well-fitted blazer adds a touch of class to any business-casual outfit, according to Kenger.

"Tailoring is a good move here, as is investing in a piece with a neutral color like navy, black, or charcoal gray for maximum wearability," the designer told BI.

Sweaters have been a go-to for decades of professionals, according to Huber. Plus, they're comfortable and layer nicely.

"I would recommend a fitted sweater that is not too baggy or oversized — otherwise, it makes it feel a little too casual, like loungewear," the designer told BI.

Casual sandals, like flip flops or slides, are never considered business casual, according to Jamie Lewin, fashion designer and founder of Vetted.

Consider more formal footwear options such as loafers or ballet flats, which can provide similar comfort levels without sacrificing style.

According to Britt Barkwell, designer and cofounder of T. LINE, graphic or slogan T-shirts are often considered distracting.

"You never want your clothing choices to start a conversation," she told BI.

Instead, Lewin recommended pairing a plain round or V-neck T-shirt with a blazer if you're after comfort.

Oversized or distressed denim shouldn't be worn to work, according to Barkwell. Instead, reach for a more appropriate fit and wash.

Huber recommended classic dark-wash denim without any embellishments.

Avoid wearing baseball caps when you're in an office environment.

"A business environment, even business casual, is the time to ditch the hats," Huber told BI.

According to Lewin, athleisure should never be worn to the office — save the workout-appropriate clothing for the gym or running errands.

Huber recommended finding a comfortable pair of slacks or dark jeans and replacing a sports-bra tank top with a camisole for layering.

Crop tops may be trendy, but they're too casual for a professional setting.

Instead, Kenger recommended a tailored sleeveless blouse or a lightweight shell tank under a blazer.