N.Y. PBS Law § 41

§ 41. Finality of certain utility charges. 1. Notwithstanding any\nother provision of law, no utility corporation or municipality may\ncharge a residential customer for gas or electric service which was\nrendered more than six months prior to the mailing of the first bill to\nthe customer for such service unless the failure of the corporation or\nmunicipality to bill sooner was not due to the neglect of the\ncorporation or municipality or was due to the culpable conduct of the\ncustomer. If the customer remains liable for such service, the utility\nshall permit payments to be made under an installment payment plan,\nprovided, however, that the utility or municipality may require prompt\npayment if the non-billing resulted from the culpable conduct of the\ncustomer. Any such installment payment plan may provide for a\ndownpayment of up to one-half of the amounts due from the customer, or\nthree months average billing, whichever is less.\n 2. Notwithstanding any other provision of law, a utility corporation\nor municipality may not adjust upward a bill previously rendered to a\nresidential customer after the expiration of twelve months from the time\nservice to which the adjustment pertains was provided unless (a) failure\nto bill correctly was caused by the customer's culpable conduct or was\nnot due to the neglect of the utility or municipality; (b) such\nadjustment is necessary to adjust a budget payment plan; or (c) there\nwas a dispute between the utility or municipality and the customer\nconcerning the bill during the twelve-month period. A utility or\nmunicipality issuing an additional or increased bill charging for\nservices rendered twelve or more months prior to such date of issuance\nshall include with it a notice giving the reason for the late billing.\n 3. No public utility company or municipality may render a bill for\npreviously unbilled service, or adjust upward a bill previously\nrendered, to a residential customer after the expiration of twenty-four\nmonths from the time service to which the bill or adjustment pertains\nwas provided. This provision shall not apply when the culpable conduct\nof a customer caused or contributed to the failure of the company or\nmunicipality to have rendered a timely or accurate billing.\n