"My Accountant" service will remind you of that. It depends on your company’s revenues. If your revenues exceeded 2,5 mln euros, then the accounting period is 1 month. If not - the accounting period is 3 months. At the end of the accounting period you will get a new task (and push messages about this) and you will need to answer a few questions and after that all your documentation and transactions will be passed to your accountant at BDO.
Attention! You have to close the accounting period before the 10th day of the month following the closing period. For example: if your period is a quarter (3 months), then you have to close first quarter before 10th of April.