The bill creates new law by adding sections to chapters 48.18 and 48.19 RCW that require insurers using a wildfire risk score or catastrophe model for underwriting or rating residential personal lines property to give specific disclosures, file models with the Insurance Commissioner, incorporate or account for mitigation actions, and establish a consumer appeal and score-revision process. Insurers must disclose in writing, in plain language, when a policy is nonrenewed or canceled for wildfire risk or when premiums are adversely impacted by a wildfire risk score: the current wildfire risk score, the score range, the entity and date of the score, and the key factors that adversely contributed to the score (with steps to improve consumer-controllable factors and a list for factors outside consumer control). When premiums are affected, that information must be provided in the renewal notice; insurers must also post publicly available information on their website about available discounts, incentives, or adjustments for property-specific or community-level mitigation and the appeal process. The bill creates procedural requirements and deadlines: a policyholder may request a revised wildfire risk score or classification once per policy period and the insurer must provide the revision no later than 20 business days after receiving a request with required documentation of mitigation; a policyholder may appeal an inaccurate score, classification, or mitigation discount once per policy period, and insurers must acknowledge an appeal in writing within 10 business days and issue a written reconsideration and decision within 20 business days, and must forward appeals and responses to the Commissioner upon request. It requires insurers to file wildfire risk models, model descriptions, actuarial justifications for rating factors (including mitigation discounts), and explanations of model use as part of a complete rate filing before using models to set premiums, and to provide data on how models account for statewide and local mitigation activities as established by rule. Model filings and related information are confidential and treated as trade secrets under RCW 48.02.120(3) except that the Commissioner may make them public for enforcement actions. The Commissioner may adopt rules to implement the new sections. The bill includes definitions for terms such as "adversely impacted," "wildfire risk score," "catastrophe model," "community-level mitigation action," "property-specific mitigation action," and "wildfire risk model," and references existing RCW notice provisions (RCW 48.18.2901 and 48.18.290) and confidentiality provisions (RCW 48.19.040(5) and RCW 48.02.120(3)). The text provided does not define "residential personal lines property insurance" within the new sections, does not reproduce the content of the cited RCW provisions, and does not specify timelines or procedures for the Commissioner's rulemaking or detailed confidentiality procedures beyond the stated limits.

If enacted, homeowners and renters with residential property insurance would get clear, written explanations when wildfire risk scores raise their premiums, cause nonrenewal, or lead to cancellation, including the score, model creator and date, and controllable steps to improve the score. Policyholders could request one re-score or classification change each policy year (insurers must respond within 20 business days) and file one appeal per year that insurers must acknowledge in 10 business days and decide in 20 business days, which gives consumers a defined, relatively quick path to challenge or improve costly insurance outcomes but may require them to document mitigation work to qualify. Insurers would face new ongoing administrative and actuarial duties: filing their wildfire risk models and justifications with the Insurance Commissioner before using them, showing how models or pricing account for property and community mitigation, posting available mitigation discounts and appeal processes online, and handling re-score and appeal timelines; these requirements will raise compliance and modeling costs, increase regulatory scrutiny, and limit insurers’ opacity about how scores affect rates (the models are confidential to the commissioner but must be filed). Some important details are missing here—such as the exact scope of “residential personal lines property,” how rulemaking will specify required data, and commissioner procedures—so how burdens and timelines play out in practice has some uncertainty.