BJP supporters danced to the beats of drums, hoisted party flags on their houses with "Everyone is in such a celebratory mood.
The people are excited and the energy here is electric," Kavita Sharma, a BJP worker, said in Delhi.
Some workers from neighbouring cities like Gurgaon, Rohtak and Noida also headed for Delhi's BJP office where they watched live telecast of Modi's swearing-in ceremony on a LED screen.
"I am ecstatic to be here on such an important occasion. Today is a memorable day. Narendra Modi is our leader and he will take India to new heights," said Shambu, a BJP worker who had travelled from Rohtak.
In UP, BJP workers distributed sweets among school children in Ghaziabad and other districts. BJP workers organised several events in Modi's home state of Gujarat.
