I’m the treasurer of an organization and for a number of years have pre-purchased oil. In the past, the amount paid has not included the sales taxes that are incurred as the oil is delivered, the company simply has deducted it from the amount I have pre-paid. This year the oil company has a new software system which will not deduct the sales tax and they are billing as oil is delivered (which is fine with me). When I called to inquire about the change, the person mentioned they will likely include the sales tax in the next year’s pre-buy amount. My understanding is sales tax is incurred upon receipt of goods and I should not be required to pre-pay potential sales tax. Am I correct in pushing back on this?