N.Y. Comp. Codes R. & Regs. tit. 7, § 720.5
(a) Outgoing mail.
Outgoing inmate mail shall be collected from mail boxes, placed in convenient locations in the facility, by a correctional employee at least once a day, except Saturdays, Sundays, and State and postal holidays; mail service on Saturdays and State holidays is optional. At no time shall an inmate collect the mail. Collected mail shall be processed and forwarded to a post office at least once a day, except as noted above.
(b) Incoming mail.
Incoming general correspondence will be delivered to inmates on normal business days by a correctional employee. Inmates are not permitted to deliver mail to other inmates.