CRA requires corporations, under certain circumstances, to prepay their income taxes for the next year.  Gernerally, if you owed less than $3,00 last year or will owe more than $3,000 this year, you are required to prepay your taxes in the current year.  For small Corporations, you can pay them quarterly, but they can also be paid monthly.  Link directly to the CRA website to get all your answers... call me if you have any questions!