What is the difference between accounting year and accounting period?

An accounting year refers to a specific 12-month period used for financial reporting and tax purposes, often aligning with a company's fiscal year. In contrast, an accounting period is any duration of time, whether it's a month, quarter, or year, over which financial transactions are recorded and reported. Essentially, all accounting years are accounting periods, but not all accounting periods are a full year. The choice of accounting periods allows businesses to assess financial performance on a shorter timeframe, if needed.