Delaware Code
Chapter 56A. Voting by mail ballot [For application of this chapter, see 83 Del. Laws, c. 353, § 6]
§ 5609A. Time limit for return of ballot; late ballots [For application of this chapter, see 83 Del. Laws, c. 353, § 6].

(a) The Department shall record the date and time of receipt on the ballot envelope of each mail ballot received.
(b) For a mail ballot to be counted under this chapter, the elector shall return the elector's marked ballot to the Department before the polls close on the day of the election.
(c) The Department shall retain unopened any ballot envelope received after the polls close on the day of the election it receives after the polls close on the day of the election until the last day of February next after the election, or longer if directed by proper authority or required to do so by federal law.

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