The bypolls were necessitated due to the death of sitting members Ramachandra Prasad, Badshah Prasad Azad and Ramashray Prasad Singh in January this year, an EC statement said.
The notification for the bypoll will be issued on April 22 and the last date for filing of nominations is April 29.
Nominations will be scrutinised on April 30 and the last date for withdrawal of candidature would be May 2.
The elections will be held on May 9, if necessary, and the results will be announced the same day, the EC said.