Election commissioner Somchai Srisuthiyakorn said a number of advance vote polling stations in Bangkok and southern provinces were closed on Jan 26 as a result of rallies by anti-election protesters.
Many who registered for advance polling were unable to cast their votes as a result, so those in affected areas will be able to try again on Feb 23.
Mr Somchai said a new round of voting would also be called for any polling units unable to open for voting on the main election day, Feb 2.
Ballot papers are yet to be delivered to various constituencies in the South after protesters blocked three large post offices responsible for distributing the slips.
Mr Somchai said the EC is negotiating with the protesters responsible. The EC has until Feb 1 to secure the release of the ballots, he added.