2015 New York Laws
CNT - County
Article 24 - (County) PROVISIONS APPLICABLE TO NEW YORK CITY
902 - Certain office hours.

 902. Certain office hours. 1. The offices of the county clerk in the
  counties  constituting  the  city  of New York shall remain open for the
  transaction of business from  nine  o'clock  in  the  forenoon  to  four
  o'clock  in  the  afternoon  every  day  except  Saturdays,  Sundays and
  holidays and except in the months of July and August when  said  offices
  shall  remain  open for the transaction of business from nine o'clock in
  the forenoon to two o'clock in the afternoon except  Saturdays,  Sundays
  and holidays.
2. Whenever the last day on which any paper shall be filed or act done
  or  performed  in  any  such  office expires on Saturday, Sunday, public
  holiday or a day when such office  is  closed  for  the  transaction  of
  business, the time therefor is hereby extended to and including the next
  business day such office is open for the transaction of business.
3. Notwithstanding the foregoing provisions of this section, the motor
  vehicle  section  of a county clerk's office may, by order of the mayor,
  be kept open on Saturdays during the month of January.