Margaret of Cortona is quickly becoming one of my favorite Saints. However AFAIK according to Wikipedia she's not canonized by the Anglican communion as my other Patron Saints I've been doing intercession for years with are. What is the Church of England's official statement on her?
The CofE does not have a formal process of canonization. (One could argue that King Charles the Martyr was a possible exception.) Margaret of Cortona does not appear in the CofE's Common Worship calendar. She is however included in the (Anglican) Society of St Francis 'Franciscan Eucharistic Supplement' where she is commemorated on May 16th. Here is the Collect: God of mercy, give us grace that we may truly repent of our sins following the example of your servant, Margaret of Cortona; and that, by a living faith, we may obtain full forgiveness; through the merits of Jesus Christ our Lord who is alive and reigns with you, in the unity of the Holy Spirit, one God, now and for ever. Amen. (The Society of St Francis publication 'Celebrating Common Prayer' greatly influenced the CofE's 'Daily Prayer' as found in Common Worship.) I live in Cornwall where many of our churches are dedicated to Celtic Saints of the 5th & 6th centuries - the majority have probably never been officially canonized but have been revered down the years and are popularly regarded as Saints. Only one or two of these appear in the Common Worship Calendar. Our Cathedral Church however commemorates these Celtic Saints in its daily celebration of the Eucharist. The more important ones such as St Pyran, St Petroc and St Sampson get a solemn celebration with bells and smells.