For electors participating in the National Assembly by-election, PCR tests for Covid-19 are not compulsory.
The Election Commission said, however, that separate arrangements were made for Covid-19 infected voters.
The decision seeks to ensure that voters exercise their voting rights under any circumstances, said Dilli Ratna Shrestha, election officer.
Members of the Bagmati Province Assembly as well as heads and deputy heads of local levels are eligible voters. Vote commences from 9 a.m. to 3 p.m.
Home Minister Ram Bahadur Thapa from the ruling CPN (UML) Krishna Gopal Tamang and independent candidate Khim Lal Devkota have been contending for the by-elections.
Minister Thapa and UML leaders such as Gokul Prasad Baskota and Krishna Bahadur Rai reached Hetauda for by-elections on Wednesday, among others.