The 2025 Cost Convention: An Updated Approach to Personal Injury Legal Costs in Ontario

Personal Injury litigation is expensive! Thankfully, our Ontario Courts mandate the Defendant contributing to the Plaintiff’s legal costs whenever a case is successfully advanced (called partial indemnity costs). 

How much the Defendant contributes toward the Plaintiff’s partial indemnity costs is intended to be related to the magnitude of work done. However, the personal injury industry has simplified matters by introducing a Cost Convention designed to estimate a fair contribution toward the Plaintiff’s legal costs without the need to have the cost contribution considered and quantified by a Judge or assessment officer.

For the last few decades, the Cost Convention has been frozen at 15% of the first $100,000 paid in damages plus 10% of the damages paid above $100,000.

To better recognize the amount of front-end work associated with getting any claim off the ground and to align the cost convention with the increased Simplified Rules threshold of $200,000, a 2025 Cost Convention is being introduced. 

The 2025 Cost Convention is for partial indemnity costs to be paid of 15% of the first $200,000 paid in damages plus 10% of the damages paid above $200,000. HST is always added to these cost contributions, as are assessable disbursements.

It is hoped that the 2025 Cost Convention better recognizes appropriate cost contributions in a manner that avoids the time and expense of having costs fixed or assessed by the Court or an assessment officer.

To help introduce the 2025 Cost Convention, a special Excel-based Calculator is now available for free at this link (referred to as the Merkurator Mediation Genie). The software, which is one small part of the Ontario Personal Injury Calculator formerly licensed by Darcy Merkur of Thomson Rogers to Thomson Reuters, can calculate both the new and old Cost Convention and provides other cost contribution options as well.

The following are available for FREE downloads:

1. Merkurator Mediation Genie (for all)

This version is suitable for mediators, insurance defence counsel, insurance adjusters and claimants. It does the math for cost plus offers and/or all-inclusive settlement offers.

Download the Merkurator Mediation Genie (for all)

2. Merkurator Mediation Genie (for Plaintiff’s Counsel)

This version is suitable for personal injury Plaintiff’s counsel and claimants. It does the math for cost plus offers and/or all-inclusive settlement offers, as well as calculates fees paid in accordance with Contingency Fee Agreements and/or other retainer agreements.

Download the Merkurator Mediation Genie (for Plaintiff’s Counsel)

3. The Ontario Personal Injury Damages Calculator 2025 (aka OPIDC 2025 or the “Merkurator”)

This is the full program previously available from Thomson Reuters used by hundreds of personal injury lawyers throughout Ontario. The software is ideal for quantifying the value of a personal injury claim. It can calculate statutory deductibles, contributory negligence reductions, prejudgment interest, discount rates, life expectancies and much more. It includes the Mediation Genie page as well as a Direction and Account option.

To download this version, please fill out the form below: