At a minimum you will need to balance your books at least once a year for tax purposes. You may also want or need to balance your books so you can provide financial statements to your company stakeholders or for certain lending institutions (that have loaned your company money). Trying to balance your financial books a full year at a time can many times prove to be a very difficult, time consuming task. Typically, a better practice is to perform a series of monthly accounting / balancing procedures--and then to 'close' the period you have just balanced--which will lock your changes into place, so your financial books will stay in balance month by month. Following this practice will make the task of balancing your financial books for a full year a much easier task.