[Jury's been out on a long recess since the Middle Ages. Orthodox pray for the dead, which implicitly recognizes purgatory, otherwise it would make no sense, and there was a kind of primacy in the preschism Church.]
From 'The Complete Book of Orthodoxy' regarding the Orthodox Catholic view of Purgatory -
The doctrine developed slowly in the Western Church and is not accepted by the Orthodox Catholic Church, which denies the "suffering of souls" in Purgatory. If there is, any suffering in the after life, some Orthodox Catholic theologians teach, it is of a purifying nature and not punitive. Others prefer to leave the entire concept alone as a mystery to which we should not attach human norms.
From "The Historical Dictionary of the Orthodox Church"
[When you look up 'purgatory' it references you to APOCATASTASIS.]
APOCATASTASIS: Fully, apocatastasis paton is "the restoration of all things." The source of this phrase i.e., that all things and beings (angels, and demons included) will ultimately be restored to unity with God, is I Cor. 15, when God will be "all in all." Its best known advocate was Origen of Alexandria, though Gregory of Nyssa a century later echoed the latter's views on this issue. The proposal that hell cannot be eternal is surely to be ascribed to a certain optimism, with origins in Platonism, that evil cannot reasonably have the last word for any rational creature. Although this doctrine was condemnedby the Council of Constantinople (553), it took the work of Maximus the Confessor a century later to demonstrate that true respect for the depths of human freedom requires the possibility of an everlasting perdition. Fear of a revival of the doctrine also lay behind the initial Greek reaction to the Latin Church's doctrine of purgatory, worked out in the 13th century. The latter's "purifying fire" smacked all too much for the Greek bishops at the Reunion of Ferra-Florence of Origen's view that hell was temporary. While it is possible to give an Orthodox reading of the Latin teaching, it is also the case that the latter, based as it was (is?) on an idea of penalty and satisfaction, would itself have to undergo a certain evolution in order to satisfy Orthodox concerns.
Why Orthodox Catholics pray for the dead. from "Dance, O Isaiah"
Question: Are there prayers for the dead prescribed in the Bible?
Answer: Yes. Praying for the dead is a duty imposed by the Bible. we are told -
'First of all, then, I urge that petitions, prayers, intercessions, and thanksgiving be made for all men, (i Tim 2:1)
that is to say, for both the living and the dead, because to the Lord there is no distinction -- "to Him all are living" (Lk. 20:38).
Question: But are explicit prayers for the dead found in the Bible?
Answer: Yes. We read that it is good "to pray for the dead....that they might be delivered from sin." (2 Macc. 12:42-45).
Question: Were prayers offered for the dead in the very early Church (1st and 2nd century)?
Answer: Yes, they certainly were. The Liturgy of St James (generally believed by scholars to have been largely formed prior to A.D. 200) offers a prayer that God will 'give rest there in the land of the living" to the deceased righteous "who are of the true faith" (36)
Tertullian in about A.D. 204 mentions Christian offerings for the departed (De corona militis). He describes it as a long standing custom and not someting newly introduced.
The epitaph (composed by himself) of St Abercius, Bishop of Hierapolis in Phrygia (died about A.D. 175) asks Christian passersby to pray for him. Also, from the 2nd century, other inscriptions on Christian tombs (notably the Roman catacombs) ask for prayers for the departed.