India's general election will take place in seven phases over April and May, the Election Commission says.
The results will be announced on 4 June, Chief Election Commissioner Rajiv Kumar told a news conference.
With some 968 million eligible voters, India's election will be the largest the world has seen.
Opinion polls predict a win for Narendra Modi's Bharatiya Janata Party (BJP) and its allies, which is eyeing a record third term in power.
More than two dozen opposition parties, including the Congress, have formed a coalition bloc - called the Indian National Developmental Inclusive Alliance or INDIA - to take on the BJP at this election.
India's lower house has 543 elected seats and any party or a coalition needs a minimum of 272 MPs to form a government.
The BJP, led by Mr Modi, had won a staggering 303 of the 543 seats in the 2019 election. This year, the party says its target is to win at least 370 seats.
Some states will hold polls in several phases.
Voting will be staggered, beginning on 19 April and ending on 1 June, Mr Kumar said.
"We will take democracy to every corner of the country," he said.
"It is our promise to deliver a national election in a manner that we... remain a beacon for democracy around the world."
Some 968 million people - 150 million more than the last elections in 2019 - are eligible to vote.
"Over 26 million new voters have been included in the electoral roll, of which approximately 14 million are women, surpassing the newly enrolled men by over 15%," the Election Commission said.
Electronic voting machines will be used and will contain a None of the Above (Nota) button.
India appointed two new election commissioners on Thursday to fill vacant spots in the three-person Election Commission.
Days before the poll dates were announced, the sudden resignation of Arun Goel, the second-highest officer in the Election Commission, had left the poll body with only one of the three mandated members, the chief election commissioner.
Meanwhile, India's Supreme Court continues to hear a case regarding the controversial electoral bonds scheme that allowed people and companies to make political donations anonymously.
The Election Commission hasreleased a listof India's leading political donors. Mr Modi's BJP was the biggest beneficiary, securing almost half of the bonds worth 120bn rupees donated between 2018 and 2024.
