The corporate tax return is filed within the 25 calendar days following the six months after the close of the fiscal year: with a calendar year, from 1 to 25 July. What that tax covers and how it works is explained in the glossary entry Impuesto de Sociedades.
For an autónomo there is no choice: personal income tax always runs on the calendar year. A split fiscal year is an option for companies, useful for example for seasonal businesses that prefer to close the books when activity is quiet. The first fiscal year of an SL is usually shorter than a full year, because it starts on the day of incorporation and ends on the closing date set in the bylaws.
The typical mistake is changing the closing date without amending the bylaws, or doing it and forgetting that the annual accounts, their approval and their filing with the Registro Mercantil move as well. Another common slip is mixing invoices from two fiscal years in the books: whatever accrues after the close belongs to the next year, even if the invoice arrives late.
The fiscal year sets the period of the journal, the balance sheet and the profit and loss account, and also the calendar of corporate tax instalment payments. In kontora double-entry bookkeeping is closed by fiscal year, and returns are prepared with deadline reminders based on your closing date.
Related terms
Rather have this calculated for you?
kontora generates your tax forms box by box, tells you how much to set aside and reminds you before every deadline.