R.I. Gen. Laws § 17-20-2: Eligibility for mail ballots.

Any otherwise qualified elector may vote by mail ballot in the following circumstances:

(1) An elector, within the State of Rhode Island who is incapacitated to the extent that it would be an undue hardship to vote at the polls because of illness, or mental or physical disability, blindness, or serious impairment of mobility;

(2) An elector who is confined in any hospital, convalescent home, nursing home, rest home, or similar institution, public or private, within the State of Rhode Island;

(3) An elector who will be temporarily absent from the state because of employment or service intimately connected with military operations or who is a spouse or legal dependent residing with that person, or a United States citizen who will be outside of the United States;

(4) An elector who chooses to vote by mail for any reason.