When do you need a business interruption claim calculated?
Common triggers we see:

• Fire, flood or water damage that forces a full or partial shutdown, including the flooding across the GTA covered in our Toronto floods coverage
• A cyberattack or ransomware event that halts operations
• A supplier or supply chain failure that stops production
• Property damage from a third party, where the interruption loss becomes part of a litigation claim rather than only an insurance claim
  A dispute with your insurer over the size, length or validity of an existing claim
• The earlier we're involved, the stronger the record. Waiting until the claim is already contested makes it harder to reconstruct what "normal" looked like before the loss.

How is a business interruption loss calculated?

The baseline period. We start from historical financial performance, generally the one to two years before the loss, adjusted for seasonality, known trends and anything unusual in that period that would distort a straight average.

Continuing versus non-continuing expenses. Costs that kept running during the interruption, such as rent, insurance and core salaries, are typically recoverable. Costs the business stopped incurring, such as suspended marketing spend or laid-off hourly staff, typically are not. Sorting expenses into the right category is one of the most commonly disputed parts of a claim.

The period of restoration. This is the window the loss is measured over, from the day operations were forced to stop to the point the business could reasonably have been back to normal. Reconstruction and repair projects routinely run longer than the original estimate, and how long a "reasonable" restoration period should be is one of the most common points of dispute between policyholders and insurers.

Mitigation. Insurers expect a business to take reasonable steps to reduce its own losses. What counts as reasonable, and whether a short-term saving (like laying off experienced staff) creates a larger long-term cost, is frequently contested and needs to be addressed directly in the report, not left for the other side to raise first.

Documentation. A strong claim is built on profit and loss statements and balance sheets covering at least two pre-loss years, payroll records, sales records, lease and supplier contracts, and inventory records. Businesses that keep a second copy of these records off-site or in the cloud are in a stronger position when the physical records are part of what was damaged.

What makes a business interruption claim defensible?
Two businesses with identical losses can end up with very different outcomes depending on how the loss is presented. The most common points where a claim gets challenged, by an insurer's adjuster, opposing counsel, or an appraisal panel, are the choice of baseline period, the classification of continuing versus non-continuing expenses, and the length of the restoration period. We build the calculation to withstand challenge on all three from the outset, with the underlying data and assumptions documented and ready to produce.

Where the claim is heading to litigation or appraisal rather than a straightforward insurer negotiation, we also prepare the report to the evidentiary standard the matter requires, coordinated with your lawyer from the start. If the insurer has already produced its own lost profits calculation, we review its methodology and prepare a rebuttal that tests the assumptions behind it, not just the final number.

Who works on your file?
Your file is led by Dave Oswald, CPA, CA, CFE, founder of Forensic Restitution.

Why work with an Oakville forensic accounting firm on a business interruption claim

A local forensic accounting firm understands the businesses and insurers operating across Oakville, Toronto and the rest of Ontario, and has seen how local events, from the GTA floods to regional supply disruptions, play out in a claim. That local context matters when an insurer's adjuster is weighing whether a restoration timeline or a mitigation decision was reasonable for a business of your size and sector in this market.

Forensic Restitution treats business interruption work the way we treat litigation support: the report is written to be tested, not just accepted. Every assumption in the lost profits calculation, the baseline period, the expense classification, the restoration window, is documented with the underlying working papers behind it, so it holds up whether the file settles at the adjuster stage or ends up in appraisal or court.

 
Key takeaways

• Business interruption losses are measured against a "but for" baseline, usually built from one to two years of pre-loss financial performance.
• Continuing expenses (rent, core salaries) are typically recoverable; non-continuing expenses (suspended marketing, laid-off staff) typically are not, and this classification is a common point of dispute.
• The period of restoration, and how long is "reasonable" to rebuild or recover, is one of the most frequently contested parts of a claim.
• Keeping financial and operational records backed up off-site strengthens a claim before a loss ever happens.