I have put mine in the dishwasher along with dishes and it has come out clean. I have done this numerous hats and no damage or shrinkage as a result. Other than that, the only other way I know of is to take it to a professional cleaners and have it dry-cleaned. Costs more that way, but that also works.

When you use the dishwasher...do you use the top or bottom rack?  Also, do you leave in the heat/dry cycle or take it out and air dry?  Thanks,

What I do is, Take some Oxy-Clean or a little bleach in water. I use one of those club cleaning brushes with the nylon bristles.

You can let it soak in the water if it is really dirty, If not just run some cool water over the hat and use the brush to scrub the dirty areas. Rinse with clean water and then take it outside and set it on something out in the sun, ( this helps to whiten it also).

I would imagine this time of year you might only have a few days of nice weather but as long as the sun is shining and it is not below freezing you should be ok.

try woollite delicate cloths cleaner use a damp tooth brush or a finger nail brush. rub gentlely!!!