The EC was responding to a comment made to Thai PBS by the deputy managing director of Thailand Post, Pongsatorn Wisetsuwan, on Friday, who said that the provincial and constituency codes on some 300,000 envelopes of advance ballots were illegible.
In the video interview, Pongsatorn said the envelopes need to be examined by the EC to determine where they should be delivered.
The commission said that the provincial and constituency codes on the envelopes had been written by different election officials at polling stations, so the writing style may have been different and sometimes difficult to read.
It added that when this problem was discovered, EC officials working with Thailand Post closely checked the codes and made sure they were delivered to the correct address. It insisted that there were no envelopes pending with the post office.
A total of 2,235,830 voters registered to cast their votes early on May 7, one week before the actual general election date. Of the advance voters, 2,216,951 had voted outside their household constituencies and the remainder in their hometowns.