Leaders and core members of political parties turned up at city hall in Bangkok's Din Daeng district on Tuesday to register their candidacy for the May 14 general election under the party-list system.
For this election, the House of Representatives has 500 members - 400 elected from constituencies and 100 from party lists.
Each party can submit a list of up to 100 candidates.
The Airawat Pattana building in Din Daeng is the designated venue for party-list registration, which continues until Friday.
Members and supporters of political parties started converging on the open ground to one side of the Airawat Pattana building early in the morning, many with flowers and campaign banners.
There was a strong police presence. Entry and exit gates were secured by crowd control units of the Metropolitan Police Bureau.
Caretaker Prime Minster Prayut Chan-o-cha, the prime ministerial candidate of the United Thai Nation Party, arrived before 8.30am. He was greeted by party leader Pirapan Salirathavibhaga and Ekanat Prompan, the secretary-general. Gen Prayut has said he will not be on the party list and will stand as an outsider candidate for the premiership.
Gen Prawit Wongsuwon, also a candidate for the post of prime minister, was expected register as the first party-list candidate of the Palang Pracharath Party. He arrived about the same time. He said he was confident Palang Pracharath would get about 20 MPs under the party-list system.
Pheu Thai leader Cholnan Srikaew arrived with the party's three likely candidates for prime minister - Paetongtarn Shinawatra, Srettha Thavisin and Chaikasem Nitisiri.
Leading members of other parties who were present included Pita Limjaroenrat of the Move Forward Party, Korn Chatikavanij of the Chartpattanakla Party and Anutin Charnvirakul of the Bhumjaithai Party.
During the party-list registration process there were two rounds of lot drawing. First, the EC chairman or his representative drew queue numbers for the political parties which arrived before 8.30am. The leader or representative of each party then drew the number the party will have on the party-list ballot paper.
With the completion of the second draw, all 49 political parties which registered on Tuesday had party-list ballot paper numbers.
The numbers the major parties drew are: Bhumjaithai (7), Prachachart (11), Chartpattanakla (14), Chartthaipattana (18), Thai Pakdee (21), United Thai Nation (22), Seri Ruam Thai (25), Democrat (26), Pheu Thai (29), Move Forward (31), Thai Sang Thai (32) and Palang Pracharath (37).
