Many commercial policies begin using estimated exposure.

For example, when a Workers’ Compensation policy starts, the business may estimate:

$300,000 annual payroll

But at the end of the year, actual payroll may be:

$450,000

The premium was originally calculated using the estimated $300,000.

The insurance company may therefore calculate additional premium based on the extra $150,000 of actual payroll.

The opposite can also happen.

If the business estimated $450,000 but only generated $300,000 of applicable payroll, the audit may produce a credit, subject to minimum premiums and policy terms.