R.I. Gen. Laws § 44-5-90 — Charlestown homestead exemption

(a) The town council of the town of Charlestown is authorized to annually fix the amount,
if any, of a homestead exemption, with respect to assessed value, from local taxation
on taxable real property used for residential purposes or mixed purposes, defined
as a combination of residential and commercial uses, in the town of Charlestown, and
to grant homestead exemptions to the owner, or owners, of residential real estate,
or combination residential and commercial real estate, in an amount not to exceed
ten percent (10%) of the assessed value. The exemption shall apply to property used
exclusively for residential purposes, and improved with a dwelling containing less
than five (5) units, or real property used for a combination of residential and commercial
uses. When real property is used for mixed purposes, the percentage of the assessed
value shall be a prorated amount. The prorated amount shall be the percentage of square
feet of the parcel used for residential purposes, multiplied by the percentage of
the homestead exemption. In order to determine compliance with the homestead exemption
as outlined in this section, the town council shall provide, by resolution or ordinance,
rules and regulations governing eligibility for the exemption established by this
section.
(b) In the event property granted an exemption under this section is sold or transferred
during the year for which the exemption is claimed, the town council of the town of
Charlestown, upon approval of the town council, may provide for a proration of the
homestead exemption in cases where title to property passes from those not entitled
to claim an exemption to those who are entitled to claim an exemption.