New digital risk focus, WTW Climate Diagnostic sharpens insurers’ view of transition exposure

Edited by ad hoc news Software & Services Desk. Reviewed before publication on 06/15/2026 at 9:15 PM ET. Details in the imprint.

WTW’s Climate Diagnostic is moving further into the spotlight as insurers look for more concrete ways to quantify climate transition risk in their underwriting portfolios. The cloud-based analytics software takes emissions data, policy scenarios and sector pathways and translates them into potential losses and capital impacts on insurers’ books, positioning itself as a decision tool for underwriting, pricing and portfolio steering rather than a pure disclosure engine, according to WTW’s own product description on its official product page. The focus sits squarely on carriers with large commercial and specialty books that must respond to new climate regulations and investor pressure without simply withdrawing capacity from high-emitting sectors.

What WTW Climate Diagnostic actually does for insurers

Climate Diagnostic is designed as a software and data service that allows insurers and, in some cases, large corporates to run consistent climate scenarios across thousands of policies and counterparties simultaneously. WTW describes the tool as combining sector-specific transition pathways with company-level emissions and financial data, enabling users to estimate how different policy or technology scenarios might affect the credit quality and insurability of their portfolios over time, as set out in the firm’s climate analytics materials summarizing its climate analytics suite. In practice, this means that an underwriter can explore, for example, how a faster-than-expected phase-out of internal combustion engines or new carbon pricing rules could alter risk drivers in auto, energy or heavy manufacturing books.

The software supports multiple reference scenarios such as those from the Network for Greening the Financial System (NGFS) or the International Energy Agency (IEA), which are widely used benchmarks for stress testing climate risk in financial portfolios. According to WTW’s product information, Climate Diagnostic can be configured to align with regulatory exercises like the Bank of England’s Climate Biennial Exploratory Scenario or similar supervisory tests, and results can be exported into insurers’ internal capital models or economic scenario generators for further analysis. That positioning makes the tool less about standalone dashboards and more about feeding climate-adjusted risk measures into existing governance processes, which is a key requirement for insurers facing Solvency II, IFRS 17 and emerging local climate-risk guidance.

Data quality is central to the software’s promise. WTW notes that Climate Diagnostic can incorporate both reported and estimated emissions data, using sectoral models where counterparty-level disclosure is incomplete, while flagging uncertainty ranges so that risk managers can see how robust a given result might be. For multinational carriers, this ability to bridge patchy disclosure is crucial, because climate reporting rules still vary widely by jurisdiction and many mid-market clients do not publish full emissions inventories. The tool’s output can be sliced by sector, geography, line of business or even individual client group, enabling portfolio managers to identify concentrations of transition risk that might not be obvious from traditional premium or exposure metrics alone.

WTW also emphasizes that Climate Diagnostic is not just a risk-avoidance tool but can be used to spot potential growth areas as economies decarbonize. By showing which sectors and clients are on relatively credible transition trajectories, the software can help underwriters prioritize capacity and product development for companies that are likely to benefit from, rather than be harmed by, the move to a low-carbon economy. This framing aligns with how many large insurers now talk about climate strategy: they want to reduce exposure to stranded-asset risk while still supporting clients that are investing in cleaner technologies and infrastructure.

Integration into existing systems is another practical point for carriers. Climate Diagnostic is offered as part of WTW’s broader climate-risk and analytics platform, meaning it can sit alongside natural catastrophe modeling, asset-side climate analytics and other advisory services that WTW sells to insurers, pension funds and corporates. That bundling reflects the company’s background as a major broker and risk adviser: instead of selling a standalone point solution, WTW leverages its relationships in reinsurance broking, risk consulting and capital modeling to embed the software within broader transformation programs, where climate risk is one component of a multi-year agenda that can also include data modernization and model validation.

From a competitive perspective, the tool positions WTW against other large insurance brokers and specialist analytics firms that are also building climate-scenario capabilities for insurers. Market observers note that carriers increasingly want tools grounded in familiar regulatory scenarios and actuarial workflows rather than generic ESG dashboards, which plays to WTW’s strengths in insurance-specific modeling expertise and its long history in capital and risk consulting. For insurers that already rely on WTW for catastrophe modeling or internal model validation, adding Climate Diagnostic can be seen as a relatively low-friction way to extend existing data pipelines into the climate-transition domain.

Pricing for Climate Diagnostic is not publicly listed and typically depends on the size of the client’s portfolio, data requirements and the level of advisory support bundled into the engagement. Industry sources suggest that such climate-risk analytics solutions are mostly sold on a subscription or multi-year license basis, often combined with consulting projects to set up data ingestion, scenario design and governance. That means the software can generate recurring revenue for WTW while also creating follow-on work for its climate and capital advisory teams, which is strategically attractive in a market where many traditional broking commissions are under pressure.

In WTW’s broader software portfolio, Climate Diagnostic sits alongside other tools aimed at quantifying emerging risks for financial institutions and corporates, including cyber, geopolitical and supply-chain analytics. Management has repeatedly highlighted climate and ESG-related services as growth areas for the firm, reflecting client demand and regulatory drivers in both insurance and corporate sectors. As more jurisdictions roll out climate-stress-testing regimes and disclosure rules for insurers and banks, demand for robust, defensible modeling tools is likely to remain high, even if specific scenario frameworks and metrics evolve over time.

WTW has also used high-profile climate and insurance conferences to showcase Climate Diagnostic, framing it as a way for insurers to move beyond qualitative climate narratives to more quantitative, portfolio-level analysis. Demonstrations often focus on visualizations that show how portfolio risk metrics change under different transition scenarios, or how risk concentrations can be mitigated through underwriting adjustments, product redesign or reinsurance. While such demonstrations are inherently simplified, they serve to illustrate for boards and regulators that climate risk is being integrated into the core risk management framework rather than treated as a separate ESG reporting exercise.

Investors, for their part, have been watching how large brokers like WTW expand into software and analytics as a way to diversify revenue and deepen client relationships. Climate Diagnostic fits into that narrative by addressing a problem that is both regulatory and strategic for insurers, which tend to be sticky, long-term clients once embedded tools and advisory relationships are in place. For shareholders, the key question is less about any one product and more about how effectively WTW can scale such offerings across its global client base, particularly in Europe and other markets where climate regulation is most advanced.

WTW has highlighted climate and risk-analytics offerings, including Climate Diagnostic, in its communications with shareholders and analysts as it positions itself as a data- and software-enabled advisory firm rather than a pure intermediary. In recent investor materials, the company has stressed that demand for climate-related analytics in insurance and capital markets is one of several structural growth drivers it aims to capture over the medium term, together with trends in cyber risk, health benefits and retirement solutions, as outlined in its strategy presentations and SEC filings summarizing its strategic priorities. Shares of WTW (ISIN US9663871021) last traded on NASDAQ at around $270 in mid-June 2026, underlining how climate analytics sits within a broader push to blend advisory, broking and software-based revenue streams.

This article was a.i.-assisted and editorially reviewed. Product information without warranty; prices and availability may change at short notice. Not investment advice and not a buy or sell recommendation. Trading involves risk up to and including the total loss of invested capital.