Not sure of the number of days by law. I would think that would be contractual or at the very least State mandated.
I would suggest a call or email to the state labor board. They will take your complaint then contact the employer and give him time to respond to them. If they find he does in fact owe you, which no doubt he does, they will order him to pay you. Normally this contact from the labor board is enough to get the payment issued.
However if you are a sub contractor then you may have a different set of rules that will apply. The labor board will let you know if you fit the description of an independent contractor or not.
Hope this helps and you get paid in a timely fashion.

