In order to confirm that transmission recrudescence or importation does not occur for lymphatic filariasis (LF) after mass drug administration (MDA), the WHO recommends post-treatment surveillance. This research article covers the transmission assessment surveys (TASs) conducted at 2 to 3-year intervals after TAS-1 stop-MDA surveys. Results from the TASs indicate that elimination of transmission has been achieved in Plateau and Nasarawa, Nigeria.