N.Y. Second Class Cities Law § 21

§ 21. Office hours. Unless otherwise provided by law, the city offices\nshall be kept open for the transaction of business each day in the year,\nSundays and legal holidays excepted, from ten o'clock in the forenoon\nuntil four o'clock in the afternoon, except that the offices of\ncomptroller, city treasurer and the office for the collection of water\nrents, shall be kept open as aforesaid from ten o'clock in the forenoon\nuntil three o'clock in the afternoon. The common council may from time\nto time direct any city office to be kept open at such other hours as\npublic convenience may require.\n