I am trying to set up payment arangements for my missouri state taxes and to do so it is asking me for a PIN. where do I find this PIN?

According to the Missouri Department of Revenue:

• "A PIN number is required to set up the IIA. Your PIN number is the four-digit number in the subject line of your billing notice."

The links below contain more information:

https://dors.mo.gov/DOR/CACSGIIA/IIA/pdIIAPersonalTax.jsp

http://dor.mo.gov/cacs/