In my Young Casual post I got a comment asking how to know when a button-up shirt is ok to leave untucked and when it should be tucked in.

Dress shirts that are designed to be tucked in have tails that are different from those casual shirts that can be worn either way. The tails are made longer so you can move around, bend over, do whatever it is you need to do without worrying that your shirt will come untucked. This is great when the shirt is tucked in, but the men who wear these shirts untucked look sloppy.

GQ covered this a while ago and had a good picture showing the difference between what looks good and what doesn’t.

If you are having your shirts altered or are buying a new on and want to know whether you can wear it untucked, pay attention to where it falls on your hips. If it goes past the opening of your pockets on a pair of jeans, it’s too long. If it’s shorter than that, you’re good to wear it untucked.

You should also be aware that wearing a shirt untucked makes it seem larger and more billowy. So if it’s a casual shirt that you want untucked most of the time, you’ll have to have it brought in at the sides or even darted in the back to still get a fitted silhouette when you wear it.

If your shirt is slimmer you can get away with tails that are a little longer.

The absolute line of no return is when they hang past your crotch up front or your ass in the back. This will just look like you’re wearing a night gown and threw some pants on underneath it.