Regardless of its state of registration, since you're a resident of MA any income reported on your 1099-K is taxable by MA. The fact that your LLC is a disregarded entity means the income is reported on your personal tax return.
Income from a 1099-K is entered in the Other Common Income section of TT. Enter your 1099-K there, go through the follow-up questions, and the program will enter the information in the proper place on your federal and state tax returns.
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
