Another question...two in one day! How exciting!: How far can we go back? We've been overpaying a vendor for many years. Is it reasonable to expect a refund for several years of overpaid taxes?
Generally, you can only go back 3 or 4 years, depending on your state's statute of limitations. And yes, almost every state expects you to get the refund from the vendor. And the vendor has to give you a refund. Expect resistance, however. Unless it's something obvious, like a resale issue, they may not understand the law and fight it.
In addition, if the amount is substantial, they may have to file for a refund with the state after giving you a refund...which means a cash flow problem. And finally, asking for a refund (or credit) will probably trigger an audit, which they don't want.
Good luck. And check with your CPA.
Sales Tax Guy
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