Creates the Local Government Billing Act. Provides that the corporate authorities of a unit of local government shall bill for any utility service, including previously unbilled service, within 12 months (for residential customers) or 24 months (for non-residential customers) after the provision of the utility service. Provides exceptions to the time limits for billing when the customer prevented the utility from accurately reading the meter. Provides that the corporate authorities shall not intentionally delay billing beyond the normal billing cycle, shall label amounts attributed to previously unbilled service as such, shall prorate previously unbilled service amounts to reflect varying rates during the unbilled time, and shall provide the customer with a payment arrangement option for previously unbilled service amounts. Provides that customers may be billed for unpaid amounts that were billed to a customer before the effective date of the Act for service that was supplied to the customer before January 1, 2026. Provides that customers may be billed for unpaid amounts if the customer was notified that there is an unpaid amount before the effective date of the Act for service that was supplied to the customer before January 1, 2026. Provides that there is no time limit for the corporate authorities of a unit of local government to collect previously unbilled service attributed to tampering, theft of service, fraud, or the customer preventing the utility's recorded efforts to obtain an accurate reading of the meter.