Section 25
When day of maturity is a holiday
Chapter 2: Of notes, bills and cheques
When the day on which a promissory note or bill of exchange is at maturity is a public holiday, the instrument shall be deemed to be due on the next preceding, business day.
Explanation.— The expression “public holiday” includes Sundays: * * * and any other day declared by the [Central Government], by notification in the Official Gazette, to be a public holiday.
The Negotiable Instruments Act, 1881 (Act No. 26 of 1881). From the updated text on India Code, with later amendments. Being checked against the official copy; amendment notes are not shown yet.