Use the size chart!  My return for  the too small hat was quick & easy. Reassuring communication from the seller. They want to please. I immediately  reordered the right size. It's a wonderful hat! Cool & handsome. This hat is more delicate than my husband's everyday Aussie hat but he loves his HAVANA hat so much, he's willing to fuss over it. He gets compliments when he wears it. This will be a repeat purchase. LOVE THIS HAT!