Do any states offer a discount for paying sales tax on time?

Yes.

One of the few bright spots for online sellers who deal with sales tax are payment discounts. There are a number of states that will actually decrease the amount you owe if you pay on time or pay early. Yes, you read that right. You can actually get free money from some states. Why not take them up on their offer? 

For example, Florida offers a Collection Allowance for on-time or early filings, and you can see this credit applied at the bottom of your Expected Sales Tax Due Report titled as "Less Collection Allowance."

Here’s the list of states that offer a discount.