Business turnover is a numeric value representing total sales. It is essentially the value of sales you make in a set period. It is generally measured over a year's period, whether that's the calendar year, tax year or fiscal year. Business turnover is one of many ways to analyze the quality and efficiency of a business, and provides a nice retrospective look at the revenue for a specific time period. Turnover is another term used for what is more commonly known as gross income or total income received.