Hey, Heather! First, I want you to know you’ll never be in trouble with the IRS for a sales tax matter. The IRS is for federal taxes. Since sales tax is a state tax, the IRS is totally uninvolved. When it comes to sales tax, especially when you’re just starting out, it’s unlikely that you’re going to end up with significant penalties even in the worst case scenario. As long as you don’t ignore it & do the best you can when you file, you’re probably going to be fine! That said, YES, you need to file sales tax even if you haven’t made a single dollar - all you need to do is keep all the numbers at $0 when you file. The state just needs to know you haven’t made any sales and don’t owe them money. However, you should have either selected or been assigned a filing frequency when you registered for a sales tax license. I’d be surprised if it were monthly - most states don’t require such new businesses to file on a monthly basis. If you’re unsure, I’d go ahead & call your state’s sales tax agency & they’ll help you determine whether your filing frequency is monthly, quarterly, or annually. Now that I’m looking back at your post, I see you said you started your business in September, but it doesn’t say when you completed your sales tax registration. Have you done that yet? If not, then you’re not yet on the hook to pay sales tax because you aren’t even allowed to collect sales tax without a license!