A tartan flannel shirt is precisely the type of reliable, hard-wearing staple you can count on wearing with jeans and a sweater from the start of fall to the end of spring. And while we tend to think of tartan as an exclusively casual pattern, its uses extend beyond off-duty wear—particularly during the holiday season.

Whether you have a holiday party invite on your desk or just feel like looking a little more festive when meeting co-workers for a drink, a tartan shirt is a seamless way to introduce some seasonality into your business casual and professional  looks.

For the easiest way to upgrade a tartan shirt, match it to a pair of chinos and either a classic blue blazer or another solid-colored sportcoat. For something a bit more elevated, wear it with a solid colored suit, or even a patterned suit or jacket so long as the pattern has a distinctly different look—for instance, herringbone or houndstooth. Don’t attempt to match it to pinstripe, which is too formal, or another pattern that features checks, such as a windowpane, a glen check or a check pattern.

How to wear tartan shirts

• Always wear tartan shirts with jeans, chinos, flannel pants or a solid suit or sportcoat. 

• Sometimes wear tartan shirts with a suit or a jacket featuring a distinctly different pattern, such as herringbone or houndstooth.

• Never wear tartan shirts with pants or a jacket that features any kind of check pattern or pinstripe.