A profit-seeking enterprise shall keep sufficient and accurate account books, vouchers and accounting records to calculate its total amount of business income.
All procedures governing the aforesaid keeping, acquisition, use, maintenance, accounting treatment and other matters concerned shall be prescribed by the MOF.

The accounting system of a company shall be on the accrual basis. But a profit-seeking enterprise not organized as a company may, if there is an established custom of the business or if the volume of business is small, report to the competent tax authority to adopt a cash-basis accounting basis.
A profit-seeking enterprise not organized as a company may change its adopted accounting system but shall report the change to the competent tax authority three months prior to the commencement of the next fiscal year.

The fiscal year shall commence on the first day of January and end on the thirty-first day of December of each calendar year. However, a profit-seeking enterprise may, on account of an established custom of the business or of special circumstances arising from the seasonal nature of the business and upon the approval of the competent tax authority, change the commencing and expiring dates of its fiscal year.