Business Interruption Duration Calculator

Business interruption claims pay only through the period of restoration. This calculator sizes the duration.

Mitigation months

Rebuild months

Ramp-back months

Extended indemnity

Total BI duration

1 yr 4 mo

Covered months

1 yr 3 mo

Uncovered months

1 mo

How the math works

Duration = mitigation + rebuild + ramp. Covered = mitigation + rebuild + min(ramp, extended indemnity).

Buy at least 90-180 days of extended period of indemnity. Most owners size BI limits but forget that revenue ramp after CO is rarely instant — the extension rider is the cheapest part of a BI program and the most common gap.

Editorial noteMaintained by EveryCalc - Reviewed June 2026

EveryCalc calculators are designed for fast, practical estimates with transparent inputs and no required account. We use plain formulas, visible assumptions, and related tools so visitors can check the result from more than one angle.

Results are informational only. For financial, tax, legal, medical, construction, or other high-impact decisions, verify the output against primary sources or a qualified professional.

Learn more about our review process on the EveryCalc methodology page.

How this calculator works

What this page estimates

This Business Interruption Duration Calculator is built to give a quick, browser-based estimate for business interruption duration. Business interruption claims pay only through the period of restoration. This calculator sizes the duration. The inputs stay on the page during normal use, and the result should be treated as an estimate for planning, comparison, or education rather than professional advice.

Calculation approach

The calculator applies the standard relationship implied by the inputs, then formats the answer so it can be checked and reused. For finance tools, the most important step is using consistent units, rates, time periods, and assumptions before comparing the result with another calculator or outside quote.

Example workflow

For example, start with a realistic value you already know, change one input at a time, and watch how the answer moves. That makes it easier to tell whether the result is being driven by the main amount, the rate, the time period, or a unit conversion.

Practical checks

Use current, real-world numbers when the result affects money, health, tax, or legal decisions.
Run a low, base, and high case when the inputs are estimates.
Check the related calculators below when the next decision depends on a different assumption.

How to interpret the business interruption duration result

Best use

Use the result as a planning number for comparing payments, rates, returns, tax reserves, or cash-flow choices before you request a quote or make a commitment.

Cross-check

Compare the answer with the contract, lender estimate, tax form, brokerage statement, payroll record, or invoice that will control the real-world outcome.

Watch for

Do not rely on a single optimistic rate, return, or fee assumption. Money pages work best when you run low, base, and high cases and keep professional advice separate from the estimate.

This page belongs to the Finance calculator library, so the answer should be read in the context of the decision you are modeling rather than as a universal rule.

Before relying on this business interruption duration estimate

Most calculator mistakes come from the inputs, not the arithmetic. Use this short audit before you reuse the answer in a spreadsheet, quote, application, or important conversation.

Confirm source numbers

Match balances, rates, fees, taxes, income, and payment dates against the lender quote, payroll record, tax form, statement, invoice, or contract.

Separate cash flow from total cost

A lower monthly payment can still cost more over time if fees, interest, taxes, or a longer term are hidden in the structure.

Run conservative cases

Test at least one higher-cost or lower-return case before using the output for a purchase, refinance, investment, loan, or tax decision.

Rerun this page when the rate, price, term, fee, tax rule, income, expense, or expected holding period changes.

How to Use

Enter mitigation months (board-up, dry-out, debris).
Enter rebuild months.
Enter ramp-back months to stable revenue.
Enter extended period of indemnity months available.
Read total BI duration and expiration.

Frequently Asked Questions

What is period of restoration?

The time from loss event until property is repaired, replaced, or rebuilt with reasonable speed. BI policies pay income loss during this window. Delay by owner (slow claim, slow GC selection) does not extend it — carriers enforce reasonable pace.

Extended period of indemnity?

Optional rider extending coverage 30-365 days past period of restoration to allow revenue to ramp back to pre-loss levels. Critical for hospitality, retail, and restaurants where traffic needs months to rebuild.

Documenting duration?

Timestamp every milestone (debris, mitigation, design, permit, rough, CO, re-open). Carrier daily logs and contractor schedules anchor duration claims. Missing documentation cuts claim at the first questionable gap.