The sample we analyzed included 15,000 businesses with 10 or fewer employees. Here's the big-picture overview: the average annual cost for small business General Liability Insurance, regardless of policy limits, was just $575.16 (less than $50 per month), with a median price of $425.Most small businesses owners (almost 60 percent) paid between $400 and $600.eneral Liability: Coverage Limits Affect Cost. If you want car insurance that pays for a wide range of damage, you have to pay more for it. The same rule applies to business insurance: if you want a policy with higher coverage limits, expect to pay more than you would for bare-bones coverage.