FAQ: If I sell to customers out-of-state, do I need to return sales tax in Texas? 

I have a customer who is in Arizona. I do not charge out of state sales tax. They are insisting I must charge them 8.25% tax. Our tax rate is 6.75%. Am I required to charge them if they insist? And where do I file this on my returns if I do charge. I don't have anywhere on the sales tax form to report out of state tax that I have received. Need to know quickly