We do not collect a sales tax or use taxes for orders shipped within the US. The price you see is the price you pay. There are never any hidden fees or costs.
For states imposing sales or use taxes, your purchase may be subject to a tax unless it is specifically exempt from taxation. Some states may require online purchasers to file a sales/use tax return at the end of the year reporting all of the taxable purchases that were not taxed and to pay tax on those purchases. You can access your state's respective taxing authorities website for information as to whether your state has a tax on out of state purchases. If they do the details of how to file these returns should be found on that website.
Orders shipped to addresses in Canada are subject to sales tax.