Advance voting for the by-elections will be held on December 15, Prapun siad.
He said the EC would need a budget of Bt80 million to organise the by-elections to fill House seats vacated by Democrat MPs.
Nine Democrat MPs have resigned to lead protests against the government. Eight of them were constituency-based MPs and the other was a party-list MP, whose seat was automatically filled by the next candidate on the party-list.
The eight constituencies are Constituencies 7, 26 and 29 in Bangkok, Chumphon’s Constituency 1, Trang’s Constituency 2, Nakhon Si Thammarat’s Constituency 3, Songkhla’s Constituency 6 and Surat Thani’s Constituency 2.
Prapun said candidacy registration for the by-elections will be held from December 2 to 6.
The EC will inform the Cabinet, which will send a royal decree to set the election date for a royal command soon, Prapun said.