N.Y. Comp. Codes R. & Regs. tit. 22 § 1215.1 : JUDICIARY — Courts — Supreme Court — All Departments — Written Letter Of Engagement — Requirements

(a) Effective March 4, 2002, an attorney who undertakes to represent a client and enters into an arrangement for, charges or collects any fee from a client shall provide to the client a written letter of engagement before commencing the representation, or within a reasonable time thereafter:

(1) if otherwise impractible; or

(2) if the scope of services to be provided cannot be determined at the time of the commencement of representation.

For purposes of this rule, where an entity (such as an insurance carrier) engages an attorney to represent a third party, the term client shall mean the entity that engages the attorney. Where there is a significant change in the scope of services or the fee to be charged, an updated letter of engagement shall be provided to the client.

(b) The letter of engagement shall address the following matters:

(1) explanation of the scope of the legal services to be provided;

(2) explanation of attorney's fees to be charged, expenses and billing practices; and

(3) where applicable, shall provide that the client may have a right to arbitrate fee disputes under Part 137 of this Title.

(c) Instead of providing the client with a written letter of engagement, an attorney may comply with the provisions of subdivision (a) of this section by entering into a signed written retainer agreement with the client, before or within a reasonable time after commencing the representation, provided that the agreement addresses the matters set forth in subdivision (b) of this section.

N.Y. Comp. Codes R. & Regs. Tit. 22 § 1215.1