Rebate and concession definitions guide entitlement assessment and the authority's duty to require evidence before granting reductions. Rebate and concession are defined as reductions or relinquishments of liability or grants by authorities; rebate is a discount or deduction from a stipulated payment often returned after payment, and concession is a yielding or a grant for utilisation. Administratively, an authority receiving a rebate application must determine entitlement and amount and may require reasonable information and evidence regarding residency and income; failure to provide satisfactory information allows the authority to withhold the rebate.