New York Consolidated Laws, Public Service Law - PBS § 41. Finality of certain utility charges

1. Notwithstanding any other provision of law, if a utility corporation or municipality does not render a residential customer for gas or electric service, with the exception of a seasonal or short-term customer as defined by rule of the commission, a monthly bill for gas and/or electric services used by such customer during that monthly period, or, in the case of bi-monthly meter reads, during that month and the prior month, within three months from the end date of such monthly billing period, then, such residential customer shall not be charged for such gas and electric services which were not billed to the customer as provided herein, unless the failure of the corporation or municipality to bill sooner was not due to the neglect of the corporation or municipality or was due to the culpable conduct of the customer.  If the customer remains liable for such service, the utility shall permit payments to be made under an installment payment plan, provided, however, that the utility or municipality may require prompt payment if the non-billing resulted from the culpable conduct of the customer.  Any such installment payment plan may provide for a downpayment of up to one-half of the amounts due from the customer, or three months average billing, whichever is less.

2. Notwithstanding any other provision of law, a utility corporation or municipality may not adjust upward a bill previously rendered to a residential customer after the expiration of twelve months from the time service to which the adjustment pertains was provided unless (a) failure to bill correctly was caused by the customer's culpable conduct or was not due to the neglect of the utility or municipality;  (b) such adjustment is necessary to adjust a budget payment plan;  or (c) there was a dispute between the utility or municipality and the customer concerning the bill during the twelve-month period.  A utility or municipality issuing an additional or increased bill charging for services rendered twelve or more months prior to such date of issuance shall include with it a notice giving the reason for the late billing.

3. No public utility company or municipality may render a bill for previously unbilled service, or adjust upward a bill previously rendered, to a residential customer after the expiration of twenty-four months from the time service to which the bill or adjustment pertains was provided.  This provision shall not apply when the culpable conduct of a customer caused or contributed to the failure of the company or municipality to have rendered a timely or accurate billing.