Definition: The twelve month period over which an organization's accounts are calculated.
An accounting year, also called an accounting period, is a company’s annual financial reporting period. There are numerous kinds of reports that are based on the accounting year and critical during the year end - taxes, for example.
When you begin your accounting, it is important to determine the start and end dates of your accounting year right away.
An accounting year is typically a period of twelve months. However, an accounting year does not necessarily need to follow the start and end dates of the twelve month calendar year. Most organizations can choose to have their accounting years begin and end on any dates.
The beginning and end dates of a company's accounting year could also depend on the country in which they are located however. In the United States, for example, many companies have their accounting year begin on October 1st and end on September 30st of the next year.
For many companies however, the accounting year does run from January 1st through December 31st.