Delaware Code
Subchapter II. Citizens Over 65 Years of Age
§ 8131. Definitions [For application of this section, see 81 Del. Laws, c. 314, § 2].

As used in this subchapter:

(1) “Income” means all income from whatever source derived including realized capital gains and, in their entirety, pension, annuity, retirement, and Social Security benefits. For any tax year for which an exemption is claimed, income'' is determined to be equal in amount to the income received during the pretax year.
(2) “Pretax year” means the calendar year immediately preceding the “tax year.”
(3) “Resident'' means one legally domiciled within the State for a period of 10 years immediately preceding October of the pretax year.
a. Mere seasonal or temporary residence within the State, of whatever duration, does not constitute domicile within the State for the purposes of this subchapter. Absence from this State for a period of 12 months is prima facie evidence of abandonment of domicile in this State. The burden of establishing legal domicile within the State is on the claimant.
b. For claimants establishing legal domicile in this state after December 31, 2018, only claimants who, as of June 30 immediately prior to the beginning of the county fiscal year, have been legally domiciled within the state for a period of at least 10 consecutive years are eligible to receive a credit.
(4) “Tax year” means the calendar year in which the county real estate tax is due and payable.

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