As any small business owner knows, sales are vitally important to keep your business alive. However, not all small business owners realize how much sales they have to make to break even with their expenses they incur in their business. A simple, straightforward way to determine how many sales you must make for a period of time is to divide your gross profit (sales -cost of sales) by your sales. This percentage you must multiply by your total expenses. Whatever this number is will be the amount of sales you must make to break even.