How is business interruption loss calculated?

A practical valuation answer

Business interruption and related loss claims are usually measured by comparing what the business likely would have earned but for the event against what it actually earned, with appropriate adjustments for recovery and mitigation. Policy wording matters, so the calculation has to align with the specific coverage being claimed.

For this type of engagement, the analysis usually focuses on pre-loss historical performance, but-for forecasts and recovery period, and policy wording, exclusions, and mitigation efforts. That is how the answer moves from a generic opinion to a defensible valuation conclusion that fits the facts.

Core valuation checklist

• Confirm the valuation purpose, date, and standard of value before starting.
• Collect the records that matter most: financial statements, tax returns, ownership documents, contracts, and any relevant legal or tax materials.
• Analyze pre-loss historical performance, but-for forecasts and recovery period, and policy wording, exclusions, and mitigation efforts.
• Document assumptions clearly so the conclusion can be explained to buyers, advisors, counterparties, or the court if needed.