Group Billing – 10% Discount on Dues. Receive a 10% discount on member dues if you have 100% participation in the group billing program from your practice or institution. The Society will send one comprehensive renewal notice to include all the SPA members in your practice or institution. Contact Greg Leasure, Membership Manager, at [email protected] or 804-565-6305 to establish group billing for your member dues or to find out more about the 10% discount.