My question mainly pertains to simple orders from places like J.Crew, Sephora, etc. I buy from these sites as a resident of Pennsylvania, but the stores aren't based in PA, so do I then have to report all of these on my taxes?
Yes, according to the state. Most states are doing this now -- anything you buy out of state that you pay no sales tax on, that you would have paid sales tax on if you bought in-state, you are supposed to pay the use tax. What that is will depend on where you live and how much you buy online, and from what sites. For example, Amazon now charges New York sales tax on purchases. They are all already taxed so those would not be included. On the other hand, if you bought a computer from an out of state company that did not charge sales tax, you would include it. You really need to think about what you buy and where from and if those places already charge you sales tax or not.
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