CALCULATION OF TAXES ON RESIDENCE HOMESTEAD GENERALLY.

(a) If an individual receives one or more exemptions under Section 11.13 for a portion of a tax year as provided by Section 11.42(f), except as provided by Subsection (b) of this section, the amount of tax due on the property for that year is calculated by:

(1) subtracting:

(A) the amount of the taxes that otherwise would be imposed on the property for the entire year had the individual qualified for the exemptions for the entire year; from

(B) the amount of the taxes that otherwise would be imposed on the property for the entire year had the individual not qualified for the exemptions during the year;

(2) multiplying the remainder determined under Subdivision (1) by a fraction, the denominator of which is 365 and the numerator of which is the number of days in that year that elapsed before the date the individual first qualified the property for the exemptions; and

(3) adding the product determined under Subdivision (2) and the amount described by Subdivision (1)(A).

(b) If an individual receives one or more exemptions to which Subsection (a) of this section applies for a portion of a tax year as provided by Section 11.42(f) and the exemptions terminate during the year in which the individual acquired the property, the amount of tax due on the property for that year is calculated by:

(1) subtracting:

(A) the amount of the taxes that otherwise would be imposed on the property for the entire year had the individual qualified for the exemptions for the entire year; from

(B) the amount of the taxes that otherwise would be imposed on the property for the entire year had the individual not qualified for the exemptions during the year;

(2) multiplying the remainder determined under Subdivision (1) by a fraction, the denominator of which is 365 and the numerator of which is the sum of:

(A) the number of days in that year that elapsed before the date the individual first qualified the property for the exemptions; and

(B) the number of days in that year that elapsed after the date the exemptions terminated; and

(3) adding the product determined under Subdivision (2) and the amount described by Subdivision (1)(A).

(c) If an individual qualifies to receive an exemption as described by Subsection (a) with respect to a property after the amount of tax due on the property is calculated and if the effect of the qualification is to reduce the amount of tax due on the property, the assessor for each taxing unit shall recalculate the amount of the tax due on the property and correct the tax roll. If the tax bill has been mailed and the tax on the property has not been paid, the assessor shall mail a corrected tax bill to the individual in whose name the property is listed on the tax roll or to the individual's authorized agent. If the tax on the property has been paid, the collector for the taxing unit shall refund to the individual who paid the tax the amount by which the payment exceeded the tax due.