Massachusetts does not give you a deduction for contributions to an IRA, nor does it give you an exemption on the earnings of a ROTH IRA.
It is your responsibility to track all of the contributions that have made over the years. That would include contributions made in other states.
If you do not enter your contributions you will be taxed on 100% of the distribution.
TurboTax provides a place to account for these contributions in the Massachusetts section of your state return.
First be sure that 1099-R information is entered exactly as indicated on the form. In the MA interview when you get to the question about "Taxable IRA/Keogh distributions" ensure that you put in the contributions that have been taxed by MA already.
Technically none of the contributions have been taxed by MA already. I moved to MA last year but the contributions for my ROTH were all taxed by Ohio 6/7 years ago.
Massachusetts does not give you a deduction for contributions to an IRA, nor does it give you an exemption on the earnings of a ROTH IRA.
It is your responsibility to track all of the contributions that have made over the years. That would include contributions made in other states.
If you do not enter your contributions you will be taxed on 100% of the distribution.
TurboTax provides a place to account for these contributions in the Massachusetts section of your state return.