Amarinder Singh's party had announced its first list of candidates a day ago.
The BJP will contest 65 seats in next month's Punjab elections while former Chief Minister Amarinder Singh's new party Punjab Lok Congress has got 37 and their third alliance partner Shiromani Akali Dal (Samyukt) getting 15.
The seat-sharing pact was announced at a news conference in Delhi by Captain Singh and BJP chief JP Nadda and Shiromani Akali Dal (Sanyukt) chief Sukhdev Singh Dhindsa.
Praising Punjab as a "leader", especially in defence and food security of the country, Mr Nadda said, "Today Punjab needs special attention, it needs a double engine government and a better coordination between the centre and the state."
Captain Singh on Sunday had announced his party's first list of candidates from 22 constituencies for the February 20 state elections to the 117-member assembly, with ex-captain of Indian hockey team Ajit Pal Singh among the prominent names.
"We have given a good set of candidates with a clear focus on winnability while ensuring due representation across regions and various sections of the society," Captain Singh, who will contest from his Patiala Urban seat, said at a news conference.
Of the 37 seats in his share, 26 are from the Malwa region of the state with which Captain Singh has had strong family ties and used to be part of the erstwhile royal estate of Patiala.
The region had helped Captain Singh swing the 2007 election for the Congress with his agricultural reforms. This time, the former Chief Minister could be helped by the eventual revocation of the farm laws by the centre, his supporters said.
Releasing the first list of nominees, the PLC chief said all these candidates have strong political credentials and are well-known faces in their respective constituencies.
There is just one woman among the candidates - Farzana Alam Khan, a former Shiromani Akali Dal MLA and wife of late police chief Izhar Alam Khan, will contest from Malerkotla in the Malwa region.
Amarinder Singh had on Saturday announced his decision to fight from his home constituency of Patiala Urban.