I worked in two states. My W2 from Rhode Island lists income in Rhode Island and Massachusetts so mt Mass state taxes is combining the income

It depends.

If you lived in Massachusetts all year:

- all of your income will be taxed in Massachusetts - regardless of where you earned it

- you'd file a nonresident Rhode Island return and pay tax on the income that you earned there

- Massachusetts will give you a credit for the tax that you paid to Rhode Island so that you aren't paying tax on the same income twice

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If you lived in Rhode Island for part of the year and in Massachusetts for part of the year:

- only the income that you earned while living in Rhode Island would be taxable to Rhode Island

- only the income that you earned while living in Massachusetts would be taxable to Massachusetts

- you would file a part year return for each state