Retrospective Rating
A premium plan where the final workers comp premium is adjusted based on the insured's actual losses during the policy period, within a min/max range.
What It Is
Retrospective rating (retro) is a premium determination method for workers compensation where the final premium is adjusted based on the insured's actual loss experience during the policy period. The premium starts with a basic premium (minimum), and actual losses are applied to calculate the final premium, subject to a maximum premium cap.
The retrospective rating formula includes several components: a basic premium (the minimum the insured pays regardless of losses), converted losses (actual losses multiplied by a loss conversion factor), a tax multiplier, and minimum and maximum premium boundaries. The minimum premium protects the insurer by ensuring a floor, while the maximum premium protects the insured by capping exposure.
Retrospective rating is typically available only to large accounts — generally those with $100,000 or more in annual workers comp premium. It rewards employers with good loss control by reducing their premium when losses are low, but it also exposes them to higher costs when losses are high (up to the maximum).
Why It Matters for Brokers
Retro plans are a powerful tool for large, loss-conscious employers. Brokers placing large workers comp accounts should understand retro rating and be able to model the financial impact under various loss scenarios. A well-structured retro plan can save a large employer hundreds of thousands of dollars in a good loss year. However, in a bad loss year, the employer pays more than they would under guaranteed cost. Brokers must ensure the client understands and can handle the premium variability.
Real-World Example
A large manufacturing company with $450,000 in guaranteed-cost workers comp premium switches to a retrospective rating plan. The retro plan has a minimum premium of $315,000 (70% of standard), a maximum premium of $630,000 (140% of standard), and loss conversion factor of 1.12. In the first year, actual incurred losses are $85,000. The retro calculation produces a final premium of $355,000 — saving the company $95,000 versus guaranteed cost. In year two, a serious claim drives actual losses to $280,000, and the retro premium rises to $540,000. The two-year average is still favorable: $447,500 vs. $900,000 guaranteed cost.
Common Mistakes
- 1Recommending retro plans to employers who cannot absorb the premium variability or who do not have strong safety programs in place.
- 2Not modeling multiple loss scenarios (best case, expected, worst case) to show the client the full range of potential premium outcomes.
- 3Failing to monitor loss development during the retro period, which can cause retroactive premium adjustments years after the policy expires.
How brokerageaudit.com Handles This
Submission Intake includes a retro plan analysis module for large workers comp accounts, modeling premium outcomes under multiple loss scenarios. Policy Checker tracks retro plan parameters (basic premium, min/max, loss conversion factor) and monitors actual loss development against the retro formula. It alerts brokers when losses are trending toward the maximum premium, allowing proactive client communication.