If you don’t already separate your laundry by color, then you’re going to have to start if you want to keep your white t-shirts looking crisp and brand-new. It’s imperative that you only wash white tees with other white tees, and keep your laundry load small. Be sure to flip your white tees inside out before washing, which “keeps the outside of the garment looking fresher,” according to the director of R&D at Hanes, Mike Abbott.
As far as washing machine settings go, you’ll want to wash white t-shirts in warm water, and add the proper amount of detergent with a whitening agent to the washer to ensure that your tees stay as fresh as the day you bought them.