Eligible voters who registered to vote outside their constituencies or outside the country in previous general elections and now want to return and vote in their home constituencies have until Dec 31 to file their application for a change with the Election Commission.

Wanchai Jaisakul, deputy director of the EC's Election Administration Office, said the request can be filed at the  EC's head office and at provincial offices, as well as with all local domicile registration offices throughout the country.

Many eligible voters were not able to cast their votes in the last general election because they registered to vote outside their constituencies in previous elections, not knowing that they were required to notify the EC beforehand in order to return to vote in their home constituencies.

For the June 2 by-election in Chiang Mai's consituency 3, the EC will not make arrangements for voters to cast their ballots outside the constituency. All eligible voters, including those registered to vote elsewhere, can vote only in the constituency, Mr Wanchai said.