Some 112,000 Indonesians in Singapore can vote on April 6, but if they opt to vote by post, they have to mail their ballot paper by April 7.
About 2.03 million overseas Indonesians will vote ahead of their countrymen this year, but they will have only one ballot paper.
The Indonesian Embassy in Singapore, like in many other places, decided on April 6, a Sunday, as the polling date to allow for higher participation. Voting throughout Indonesia itself will be on April 9.
Overseas Indonesians are grouped into the same electoral district as residents of central and south Jakarta.
About half of them are in Malaysia - 1.04 million voters - many of whom are plantation workers.
But participation rates have been low. At the last election in 2009, overseas voter turnout was 22.3 per cent, and the target this year is 40 per cent, as the government plans to visit Indonesians working on these plantations, said Ambassador Wahid Supriyadi, a senior foreign ministry official who leads a team that oversees the elections abroad.
"We have notified the plantation companies there that we will come around with a drop box and ballot papers. Some of these plantations are nine hours away from where the polling stations would be," he told The Straits Times.
"So it would otherwise be impossible to expect them to come out and vote."
About a third of the voters in Malaysia, mostly professional workers, plan to come to a polling station near their area, while two-thirds would either vote by mail, or wait for embassy officials to come to them.
But the biggest challenge is in the Middle East, where many of the nearly one million Indonesians work as maids.
"Most of them do not have permission to leave the house by their employers. It is easier to approach employers in Malaysia which are plantation companies, than to approach families, as in the case of the Middle East," Mr Wahid added.
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