The notification attached by Yaasmin is not meant for private establishments but pertains to holidays declared pursuant to the Negotiable Instruments Act. However, the fact is that election day is a holiday for private establishments in the constituency. It is to be noted that the word "holiday" is used in place of "leave with salary," and it should be interpreted as leave with salary only. If all the employees in an establishment located in a constituency where an election is held are from some other place where the election is held or is to be held on a different date, there is no meaning in closing down that establishment just on account of an election.
Section 135 B
Section 135 B only says that "every person employed in any business, trade, industrial undertaking, or any other establishment and entitled to vote at an election to the House of the People or the Legislative Assembly of a State shall, on the day of poll, be granted a holiday." This shows that employees entitled to vote shall be given a holiday, and it does not say that the establishment should be closed on account of the election. You can run your establishment with employees who do not have an election. But the Negotiable Instruments Act, which applies to government services and the banking and finance-related sector, requires that such offices should not function. Declaring a holiday to an establishment is different from allowing or granting a holiday to an employee.