Indiana Code Title 6. Taxation § 6-3-4-8.1

Sec. 8.1. (a) Any entity that is required to file a monthly return and make a monthly remittance of taxes under sections 8, 12, 13, and 15 of this chapter shall file those returns and make those remittances twenty (20) days (rather than thirty (30) days) after the end of each month for which those returns and remittances are filed, if that entity's average monthly remittance for the immediately preceding calendar year exceeds one thousand dollars ($1,000).

(b) The department may require any entity to make the entity's monthly remittance and file the entity's monthly return twenty (20) days (rather than thirty (30) days) after the end of each month for which a return and payment are made if the department estimates that the entity's average monthly payment for the current calendar year will exceed one thousand dollars ($1,000).

(c) If the department determines that a withholding agent is not withholding, reporting, or remitting an amount of tax in accordance with this chapter, the department may require the withholding agent:

(d) An entity that withholds taxes shall file the withholding tax report and remit withholding taxes electronically through the department's online tax filing program.

(e) Beginning after June 30, 2021, the department shall provide a notice, by electronic means, to each employer:

The notice under this subsection shall be made by the department not more than seven (7) days after the date the employer's Form WH-1 monthly withholding tax report or employer's withholding taxes become due.  The department may provide the notice under this subsection by advising the employer to check the employer's online portal account for an important message and that the department may not have received the employer's Form WH-1 monthly withholding tax report or employer's withholding tax remittance, or both, if applicable, when due.