• September 14: The Elevation of the Cross
• December 20-25: The final period of the Advent Fast and the Feast of the Nativity of Christ
• January 5: The Paramon of Theophany
• Great Lent and Bright Week: that is, Clean Monday through Bright Saturday
• The Sunday of Pentecost
• August 1-14: The Dormition Fast
• August 29: The Beheading of St John the Baptist

The above is a comprehensive list of the prohibited days.

Any day not listed above is permitted.

(Please note that there are no longer prohibitions for Wednesdays and Fridays, the part of the Nativity Fast before December 20, the pre-Lenten period, and Thomas Sunday.)

Additionally, according to the Synodal decision, weddings on Saturdays are discouraged but not prohibited.

Prohibitions on Marriages

There are prohibitions on marriages in the Orthodox Church between
couples in the following relationships:
• Parents with their own children and grandchildren;
• Brothers-in-law with sisters-in-law;
• First or second cousins;
• Aunts and uncles with nieces and nephews;
• Godparent with godchild;
• Godfather with mother of godchild;
• Godmother with father of godchild;
• Foster parents with foster child;
• Same gender relations.