Rhode Island General Laws Title 44. Taxation § 44-30-18. Credit for income taxes of other states

(a) General. A resident shall be allowed a credit, against the Rhode Island personal income tax otherwise due for the taxable year, for the aggregate of net income taxes imposed on him or her for the taxable year by other states (including the District of Columbia) of the United States if the taxes are imposed irrespective of the residence or domicile of the taxpayer.

(b) Limitation of credit. The credit shall not exceed the proportion of the taxpayer's Rhode Island personal income tax that the taxpayer's Rhode Island income derived from the other taxing states bears to his or her entire Rhode Island income for the same taxable year. The source of income shall be determined in accordance with the rules prescribed in § 44-30-32.

(c) Readjustment of another state's tax. If the taxpayer is allowed credit under this section for more or less of another state's tax than the taxpayer is finally required to pay, the taxpayer shall send notice of the difference to the tax administrator who shall re-determine the tax for any years affected regardless of any otherwise applicable statute of limitations.

(d) Double residence. If the taxpayer is regarded as a resident both of Rhode Island and of another state for purposes of both their net income tax laws, the portion of Rhode Island tax allocable on average to the income taxed twice by reason solely of dual residence shall be reduced by the “appropriate percentage” of the lower of the two (2) state taxes allocable on average to the income taxed twice, if the other state also allows a similar reduction of its tax. The “appropriate percentage” shall be the percentage, which the Rhode Island tax is of the combined taxes of the two (2) states, allocable on average to the income taxed twice.