Who is obliged to register sales tax:
If a retailer does not have a physical presence in Indiana, but it has exceeded the threshold in the current or previous calendar year, it must register with the department.
Gross revenue from sales into Indiana exceeding $100,000, including tax-free sales;
200 or more separate transactions into Indiana.
If all of your sales in Indiana are through a marketplace platform, you can not register for paying Indiana sales tax: Your marketplace facilitator pays itself. But you should apply for an exemption certificate
Sales tax payment and filing date:
The frequency of filing a tax return depends on the amount of tax liabilities:
Annual – $83.33 or less- 30 days after the end of the frequency
Quarterly – $1,000 or less – 30 days after the end of the frequency
Monthly – More than $1,000 – 20 days after the end of the frequency
If the filing due date falls on an off-day, sales tax is due the next day. Quarterly filing periods ended last days of April, July, October, and January.
Penalty and interest:
Failure to file or pay 10% of the tax due