The two candidates have campaigned extensively to succeed President Pranab Mukherjee whose term ends on July 24.
In order to ensure a 100% turnout, the Election Commission or EC has allowed 14 Rajya Sabha MPs and 41 Lok Sabha MPs to vote in state assemblies for presidential polls today. The poll body has also allowed five MLAs to vote in the Parliament in New Delhi.
71-year-old Kovind has the support of well over 60 per cent of the vote, while Meira Kumar has the support of 17 parties. Nitish Kumar's Janata Dal United has decided to back Mr Kovind, a decision that has led to fissures in the Opposition ranks.
Here's a quick guide on how the President is elected:
The President of India is chosen by the Electoral College, which consists of 4,896 members - 543 Members of Lok Sabha, Members of Rajya Sabha (233) and total members of State Assemblies (4120).
While the Lok Sabha Speaker, an elected member, can vote, the two nominated members in the Lower House from the Anglo-Indian community cannot. Twelve nominated members in Rajya Sabha are also ineligible, news agency Press Trust of India reported.
The total value of votes in the Presidential elections is 10,98,903 - 5,49,408 for MPs and 5,49,495 for MLAs. A candidate needs to secure 50% of the valid votes polled +1.
The counting of votes will take place on July 20 in New Delhi where all the ballot boxes will be brought from various state capitals.
So far 13 Presidents have been elected to the post. In the 2012 elections, incumbent President Pranab Mukherjee, who was UPA nominee, had garnered 7,13,763 votes, while Pratibha Patil, another UPA nominee, secured 6,38,116 votes in the previous polls in 2007.
A total of 13 vacancies in Lok Sabha and state assemblies will be filled up after the presidential elections.
Read more on Presidential election here.