By-elections to one vacant seat in the Gujarat assembly and two seats in the Karnataka assembly will take place Sep 13, the Election Commission announced on Friday.
The poll panel said the model code of conduct will come into force with immediate effect.
In Gujarat, by-election will be held in Kathlal constituency, while in Karnataka it will be held in Gulbarga Dakshin and Kadur constituencies.
While the poll notification will be issued Aug 18, the last date for filing nominations is Aug 25 and the scrutiny is scheduled for the followig day, the commission said.
The last date for withdrawing candidature is Aug 28.
Counting of votes will take place Sep 16, it added.
"The commission has decided to use electronic voting machines (EVMs) in these bye-elections in all polling stations.
"Adequate numbers of EVMs have been made available and all steps have been taken to ensure that the poll is conducted smoothly with the help of these machines," the commission statement in New Delhi said.