[mjn]

Same situation in Greece. Formal documents like identity cards, university diplomas, and even mailboxes, generally put the surname first, while in running text, like a news article, the given name is first. Some formal documents also list the patronymic, in the order: Surname Given Patronymic.

In some situations it is less clear which convention applies. For example most of my older relatives use surname-first for their Facebook account name, which is less common with younger people. I have also seen both orders on business cards. I think most Greeks would not expect foreigners to be familiar with or follow these conventions though.