Postal voting explained
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Postal voting allows eligible voters to receive a ballot paper by mail, complete it away from a polling place, and return it through the postal system or a designated drop off point rather than voting in person on election day, which is not always immediately apparent, however routine it may otherwise seem.
Eligibility rules for postal voting vary considerably, with some jurisdictions allowing any voter to apply and others reserving it for people who cannot reasonably attend a polling place, such as those living overseas, in remote areas, or unable to travel due to illness, a point that deserves more attention than it gets.
Because postal ballots often arrive and are counted over a longer window than in person votes, results in a close contest can sometimes shift as postal votes are progressively counted after election night, which is a normal part of the process rather than a sign of irregularity.