Tarzana Endocrine and Medical Group has contractually agreed as a preferred provider with the commercial insurance companies that co-payments will be collected at the time of the visit. Patients agree to the same stipulation of paying their co-payment at time of service when signing for PPO insurance policies. After the insurance carrier determination of payment, patients are billed their assigned portions due the provider. Full payment is expected upon receipt of statement. Per office policy, if payment is not made within the first 30-day billing cycle, a 1.5% monthly [18% per year] finance charge is assigned to all delinquent balances.