The first consideration to make, is to make sure the accounting practices at your school allow for a credit from one academic school year to be transferred to another academic school year. If this is an acceptable practice, use the following procedure.
 
1.  Navigate to https://school.smarttuition.com.

2.  Go to the past school year with the credit balance.

3.  Go to the family account. 

4.  Apply a fee to the family account in the same dollar amount as the credit . This will $0 out the credit balance in the old year.
           5.  Apply a discount in the new school year with the exact dollar amount of the fee applied in the prior year.
                                 How do I add a new fee or discount in edit billing details?
 
Note: It is best practice to give the fee in the prior year and the discount in the new year similar names.

For example, "2016-17 Credit Balance Transferred" (in the old year) and "2016-17 Credit Balance Transferred" (in the new year).