The applications can be submitted between 8.30am and 4.30pm daily, including public holidays, the commission announced on Friday.
Candidates are required to show up personally at their nearest EC office with all the required documents, including proof of identity and proof of expertise in the field they are applying under.
As per the Constitution, senatorial applicants will come from 20 eligible professional groups, including law and justice, education, public health, agriculture, science and technology and mass communication to name a few.
For more information, visit www.ect.go.th, call the local EC office or the EC hotline at 1444 during business hours.