Beyond the Rate Change: Managing the 2026 ISO GL Transition

For US P&C carriers, adopting a new ISO rate plan involves much more than loading new rating content. The 2026 Commercial General Liability (GL) changes make the complexity of that transition particularly clear. 

The revised plan includes significant changes to the GL classification structure, with more than 55 new classifications and the consolidation of more than 130 existing classifications into approximately 60. Updated loss costs are also expected in 2026, alongside a multistate forms revision taking effect in many jurisdictions for policies written on or after October 1, 2026. 

For carriers operating across multiple states and managing complex commercial books, these changes have implications across the policy lifecycle. Existing policies need to be mapped to the new classification structure, carrier-specific pricing strategies need to carry forward appropriately, premium impacts need to be understood, and policies need to transition according to relevant state and renewal timelines. 

Successfully managing that process requires carriers to understand the impact of change across the existing book while maintaining the governance and control expected of a highly regulated business. 

The Existing Book Creates the Greater Migration Challenge 

The revised ISO GL classification structure creates an immediate question for carriers: how should exposures written under the existing structure be treated under the new one? 

Some conversions may be relatively straightforward, with an existing classification mapping directly to a new classification. Others may require information already available within the policy record to determine the appropriate destination. More complex cases may require additional information about the risk or input from an underwriter. 

Across a national commercial book, those individual decisions can quickly become a significant migration exercise. Carriers need to determine which policies can transition automatically, where existing data can support the conversion, and where additional underwriting involvement may be necessary. 

Classification decisions also connect to other parts of the insurance process. Policy data, underwriting context, pricing logic, product rules, and renewal timing can all influence how an exposure should transition. Managing those relationships becomes an important part of preparing the existing book for the new plan. 

Understand the Impact Before Changes Reach the Market 

Classification is one dimension of the transition. Carriers also need to understand what happens to premium when the new plan is applied across the portfolio. 

Pricing teams need visibility into where premium movement occurs across states, classes, industries, account sizes, and other meaningful segments. They also need to understand what is driving those changes, including revised classifications, updated loss costs, changes in exposure treatment, and the carrier's own pricing decisions. 

Comparing the existing and new rating approaches before implementation can provide that visibility and help teams identify areas requiring closer review. 

Consider an account whose premium moves from $42,000 to $49,500 under the new approach. The overall premium change provides only part of the information needed to evaluate the result. A more useful analysis shows how individual factors contributed to the movement. Classification migration might account for one portion of the increase, updated ISO loss costs for another, with revised exposure treatment and carrier-specific pricing decisions contributing to the remainder. 

Understanding those drivers gives actuarial, underwriting, product, and regulatory teams a clearer view of the transition and a stronger basis for determining how to manage its impact. 

Preserve the Carrier's Pricing Strategy 

ISO provides the foundation for many commercial insurance rating plans, while carriers build their own pricing strategies around that foundation. Those strategies can include loss-cost multipliers, minimum premiums, deductible factors, tiering, credits and debits, schedule rating, and proprietary rules. 

Preserving those decisions through the transition is critical. The new ISO structure needs to be incorporated while maintaining visibility into the carrier-specific pricing logic that has been developed around it. 

Over time, manual implementation processes can make that distinction harder to manage. ISO content and proprietary pricing logic may become increasingly intertwined, requiring teams to determine which elements need to change and which should carry forward each time the underlying content is updated. 

Keeping those layers clearly defined can make future changes easier to manage while giving pricing teams greater control over how their strategy evolves alongside ISO content. 

Plan for a Phased Transition 

For national carriers, the transition will likely unfold over time. State adoption dates may vary, existing policies may remain on the legacy plan until renewal, and endorsements or mid-term transactions may require different treatment. Certain accounts may also require additional review before moving to the new structure. 

As a result, carriers may need to support legacy and 2026 rating approaches simultaneously while directing each transaction to the appropriate version. 

This makes effective-date management, version control, testing, and monitoring important parts of the transition. It also requires coordination across actuarial, underwriting, product, technology, governance, and regulatory teams as policies move through the process. 

A clear transition strategy can help carriers manage that complexity while maintaining consistency across states, products, and renewal cohorts. 

Protect Pricing Capacity Through Change 

The 2026 GL transition creates an immediate implementation challenge while also highlighting a broader issue for insurance pricing organizations. 

The GL transition is also part of a broader ISO modernization effort, with Commercial Auto and Property expected to follow in 2027. The processes carriers establish now can provide a more repeatable foundation for managing future rating change. 

Significant pricing changes can require extensive mapping, analysis, testing, reconciliation, and coordination across teams and systems. The work is necessary, but the resources supporting it are often the same experts responsible for pricing strategy, product development, predictive modeling, and other initiatives designed to improve underwriting performance. 

The way carriers manage major updates therefore has implications for pricing capacity. More efficient, repeatable processes can reduce the amount of expert time absorbed by implementation, help carriers prepare for future ISO updates, and give pricing teams greater room to evaluate opportunities, understand portfolio performance, and refine strategy. 

For the 2026 GL transition, preparation starts with a clear understanding of the existing book. Carriers can identify classification and data challenges, evaluate the financial impact of the new plan, determine how proprietary pricing decisions will carry forward, and establish a controlled approach to implementation across jurisdictions and renewal cohorts. 

This creates greater visibility into the transition and helps teams manage change while keeping attention on the pricing decisions that support business performance. 

Preparing for the 2026 GL Transition 

Earnix Price-It integrates ISO Electronic Rating Content (ERC) to help carriers streamline ISO adoption and manage pricing change within a more connected workflow. For carriers preparing for the 2026 GL transition, Earnix can support the process from understanding portfolio impact and preserving carrier-specific pricing logic through testing, version management, and implementation. 

The goal is not simply to get the new ISO plan into a rating environment. It is to help carriers understand what will change, why it will change, and how those changes will affect the business before they reach production. 

Connect with us to learn more about how we can help your organization prepare for the 2026 ISO GL transition.