In the national capital, revellers were soaked in a riot of colours as they smeared 'gulal' (coloured powder) on each other, distributed sweets and danced to loud music.
While youngsters armed with 'pichkaris' (water guns) and balloons filled with coloured water sprayed each other as well as passersby, elders preferred to smear one another with gulal as they hugged each other and wished 'Holi Mubarak'.
"My brother and me were up till late last night and filled over 100 balloons with coloured water. Since morning, we have been targeting people with them," said 15-year-old Astha Sharma from Patel Nagar in west Delhi.
Bands of youngsters drenched in blue, green, pink, red and yellow could be seen roaming Delhi streets with colours, balloons and pichkaris as they searched for unwary people.
Many visited temples and prayed to Lord Krishna.
In the country's business hub Mumbai, the city and suburbs erupted in colours as thousands poured out of their houses and building complexes since morning to play Rang Panchami (Holi).
Chief Minister Prithviraj Chavan, Mumbai Police and film and television stars urged people to play a safe Holi.
In southern state Andhra Pradesh, Holi was celebrated with traditional fanfare and gaiety. Governor E.S.L. Narasimhan and Chief Minister N. Kiran Kumar Reddy led the celebrations.
However, the festivities were marred with the death of eight people in separate incidents across the state.
Five youths drowned in a lake in Nizamabad district. Police said they drowned in Basant Lake in Srikonda while taking bath.
A youth drowned in a well in Hyderabad, while a six-year-old boy drowned in a water tank in Nalgonda district. Another youth, playing Holi, was killed when a truck knocked him down in Guntur district.
In West Bengal capital Kolkata, 'Dol Yatra' as Holi is called there, was celebrated with traditional fervour with songs, dances and prayers.
Thousands including overseas Indians assembled at Santiniketan, about 165 km from the state capital, where Nobel laureate Rabindranath Tagore re-introduced Holi as 'Vasanta Utsav' (Spring fest) in his Visva-Bharati university.
In Bihar, Chief Minister Nitish Kumar played Holi with Janata Dal-United workers and the public and took pot-shots at Rashtriya Janata Dal leader Lalu Prasad.