N.Y. Comp. Codes R. & Regs. tit. 16, § 13.11 – Contents of bills.

(1) Only service(s) performed, materials furnished or other charges made by the utility, in accordance with its filed tariff, may be included and shall be itemized on the applicable bill form. Whenever the bill form, by reason of size limitations, does not permit itemization, totals may be utilized, provided the charges making up such totals are itemized and sent with the bill.
(2) Nothing in this section shall preclude a utility from providing pertinent messages and information on the bill, provided such information does not interfere with the presentation of the information required by this section.
(b) All bills.
Every utility bill shall state on the portion retained by the customer:
(1) the name of the corporation, partnership or person that furnished the service; and if the service is furnished by a corporation that is owned or controlled by another company, or constitutes part of a system, the bill may so indicate by the use of a symbol or a statement to that effect;
(2) the location of the utility's principal office and one or more business offices at which the bill may be paid, and a statement that bills may be paid at other authorized offices;
(3) the service classification(s) on which the charges were based;
(4) the name of the customer, the account or meter number, and the address and location of the premises where the service was supplied;
(5) the start and end date of the billing period;
(6) the quantity of service billed, the unit of measurement used, an explanation of any calculations or factors used to determine the cost of service, a description and the cost of any other tariff charges, and the total of the current charges;
(7) the date payment is due; provided, however, that such date may not occur before personal service of the bill or three calendar days after the mailing of the bill. A phrase indicating that a bill is due upon receipt may be used in lieu of a specific date;
(8) whether any charge will be imposed for late payment, and the date by which payment must be received in order to avoid the imposition of the late payment charge;
(9) an explanation of any abbreviation or symbol used that is not in common English usage; and
(10) a telephone number to call at the utility if the customer has any questions about the bill.
(c) Cycle bills.
Every utility bill issued on a regular cycle basis shall contain, in addition to the items required under subdivision (b) of this section:
(1) the registered demand for every demand meter, whether or not the customer is presently subject to a demand charge;
(2) the date of the latest payment received or the date through which any payments have been credited and the debit or credit balance carried over from the prior bill, if any;
(3) the amount of any late payment charge applied during the current billing cycle; and
(4) the next scheduled meter-reading date, except where the utility is unable to adhere to a fixed meter-reading schedule.
(d) Metered service bills.
Every utility bill for metered service shall contain, in addition to the items required under subdivision (b) of this section:
(1) for every cumulative energy and demand meter, the indices being used to calculate the bill, whether they are based on an actual reading of the meter, a remote register, a customer- provided reading, or an estimated; and if estimated, the reason therefor; and
(2) the meter multiplier or constant for each meter.
(e) Unmetered service bills.
Every utility bill for unmetered service, whether use of such service was authorized or unauthorized by the utility, shall contain, in addition to the items required under subdivision (b) of this section:
(1) a clear statement that the bill is for an estimated amount of service utilized but not metered; and
(2) the per-day or other basis used for calculating the amount of the service billed.
(f) Levelized bills.
Every levelized bill shall contain, in addition to the items required under subdivision (b) of this section, the total service charges incurred, the total of levelized bills rendered from the beginning of the levelized year to the end of the period covered by the current bill and the amount of the difference between the two.
(g) Utilities shall comply with this section no later than March 18, 1988.

(a) Generally.