I have a very large head. My hat size is 7 7/8. That's 24.5 inches. Most hats are size 7 or 22 inches. For years I searched for pretty hat in extra large sizes. The only things I could find were special order knit caps on Etsy. I always wanted a straw hat with a big floppy brim. But whenever I searched for big hats online, I would only find men's designs. This summer I tried another search. This time I found a beautiful hat at an online store that fit my wants but the sizing was for a 24 inch head. I was so sad. I looked up the manufacturer and it turns out they offer the hat in up to size 8! I ordered it and it is fantastic. It's a simple straw hat. I've tied cream lace around it and have received a lot of compliments. If you have a larger head, I highly recommend Sun Body hats.
I don't have enough posts yet to link to the site. But you can Google "Sun Body hats" to get to it.