• Income insurance is a type of business interruption insurance that uses a monthly indemnity limit instead of a co-insurance clause. The declarations show both the total insurance limit and the portion of that total limit (expressed as a fraction: one third, one quarter, etc.) applicable to the loss in each month following the direct damage loss. Monthly Insurance Claim Limit on Office Services, Inc. Insurance Forms. (ISO) for business income coverage approximates the insurance coverage provided in the form of income insurance.