R.I. Gen. Laws § 28-17-3: Tax exemption.

The intangible personal property held in any employees’ trust as defined in § 28-17-1 shall be exempt from all sales and use taxes and all other state and local taxation so long as it is held in trust and used for the purposes of the trust and of the plan of which the trust forms a part. The right of any employee or beneficiary under the plan to any pension, annuity, or retirement allowance or to the return of contributions, and any other benefit or right accrued or accruing to any person under the terms of the trust or plan shall be exempt from all local taxation and state taxation except for the personal income tax imposed under the provisions of chapter 30 of title 44.