How long after a hair transplant can you wear a wooly hat?

You can wear a hair usually a day after surgery.  If you want to wear a wooly hat just make sure it won't pull or get caught.  It is best to consult with your doctor if you are concerned.

There are two components to this: How tight the wooly hat is and what is it made up of. Cotton can actually stick to the hair follicles that were transplanted and pulled them out. If it's too tight it can stick to the grafts so I will get the loose one. I would recommend after one to two weeks. Important thing is how you put them on and how you remove it. You want to be very careful so that it won't stick to the grafts. In my practice, I generally wait after one to two weeks. Baseball hat is probably better.

İt is better to camouflage transplant area in public places by a wooly cap/cap  2 weeks after transplantation …dont use it before 10 days ...  

The grafts are pretty secure and a wool hat should not hurt the grafts after 2 weeks.  The only issue would be sensitivity to the fabric as the skin is delicate in the transplanted area and healing.  Id refrain from wearing the hat for extended periods but covering your head for short amount of time after two weeks should be fine.

Please consult your post operative instructions.  I recommend that you wait to wear any kind of fabric hat that may pull out the grafts when it is removed until 14 days.

The grafts will have healed in sufficiently with in 10 days.  You want to avoid anything on the head that could potentially dry to a fresh surgical wound (and subsequently damage grafts) prior to that.  While its true that that the wool might be a little irritating to some people, from a safety of graft / tensile strength perspective, 10 days is sufficient. 

I would wait at least 28 days post op. A wool hat can cause irritation to the scalp which you do not want to occur. 

After hair transplant a loose fitting hat can be worn immediately. A hat will not damage the grafts.

To be safe, I recommend waiting at least a week before wearing anything that may rub against the grafts and potentially do harm to them. If you must wear a hat in the first week following a procedure, it is better to wear a loose fitting hat that will not rub against the grafts. 

Many men like to wear a wool hat after a hair transplant. I generally like all of the crusts off which can occur with good washing in a day or two