New York Codes, Rules and Regulations
Title 17 - DEPARTMENT OF TRANSPORTATION
Chapter VI - Transportation Regulations
Subchapter E - Motor Carriers
Article 4 - Rates and Charges
Part 830 - Extension Of Credit By Common Carriers Of Property And Of Household Goods
Section 830.3 - Presentation of freight bills

(a) Freight bills for all transportation charges shall be presented to the shippers within seven calendar days from the first 12:00 midnight following delivery of the freight.

(b) Shippers may elect to have their freight bills presented by means of the United States mails, and when the mail service is so used the time of mailing by the carrier shall be deemed to be the time of presentation of the bills. In case of dispute as to the time of mailing, the postmark shall be accepted as showing such time.