The announcement comes after a historic meeting that took more than 55 years to organise.
Not all leaders attended, however, those there said they would like to meet every "seven-to-ten-years."
The Russian, Bulgarian, Antiochian and Georgian Orthodox churches did not send representatives.
Delegates affairms that marriage should be between a man and a woman and they also condemned persecution against Christians and they discussed the environment.
The Great and Holy Council took place in Crete and more than 200 bishops from more than ten churches affirmed their full willingness to work together as well as work with the four churches that did not attend.
Those that did not chose to attend gave reasons including unresolved disputes with other churches and not liking the procedures used for running the council.
Their message said: "The key priority of the council was to proclaim the unity of the Orthodox Church.
"Founded on the Eucharist and the apostolic succession of her bishops, the existing unity needs to be strengthened and to bear new fruits."
According to the Catholic Herald, the bodies are not calling themselves a "federation", instead they identify as one Church.
Pope Francis, the leader of the Catholic Church, has said the meeting is a "positive" step forward for the Orthodox Church.
He admitted there was not "100 per cent" participation, but said it was a move towards greater unity.
The pope went on: "Just the fact that these autocephalous churches gathered in the name of Orthodoxy to look each other in the eye, to pray together and talk - maybe making some quips - that is extremely positive, and I thank the Lord."
During their last meeting at the summit, the bishops stressed their dedication to Orthodox Christians and their will to spread the Gospel, as well as engage with people all over the world in conversations about Christianity.
About marriage, they said "in contrast to the contemporary approach to marriage, the Orthodox Church regards the indissoluble loving relationship of man and woman as 'a great mystery of Christ and the church.'"
They collectively said: "The oil of religious experience must be used to heal wounds and not to rekindle the fire of military conflicts."
The bishops spoke out against violence and persecution towards Christians and other minorities in the Middle East and said governments have a duty to accept those fleeing conflict.
Religious leaders also spoke out against environmental destruction, saying it is "connected with greed, avarice and egoism, which lead to the thoughtless use of natural resources, the filling of the atmosphere with damaging pollutants and to climate change."
They called for a Christian response to the problems facing the world today.
