On August 8, 2023, a wind-driven wildfire moved through Lahaina faster than residents could evacuate. More than 2,700 structures burned, at least 100 people died, and the fire became the deadliest in the United States in over a century. For Hawaii homeowners insurance underwriters, that event permanently changed how wildfire risk is priced and underwritten across the state. Properties that had never been flagged as wildfire exposures suddenly found themselves in a different risk tier — and some found they no longer had coverage at all.
What the HWMO Score Is and Where It Comes From
The Hawaii Wildfire Management Organization (HWMO) produces a property-level wildfire risk score used by carriers, underwriters, and the Hawaii Emergency Management Agency (HIEMA) to assess wildland-urban interface (WUI) exposure. The score draws on vegetation type, slope, aspect, historical fire perimeters, proximity to ignition sources, and local wind climatology. Properties are classified as Low, Moderate, High, or Very High (Extreme in some carrier applications).
The HWMO is not the only scoring system carriers use. Some rely directly on HIEMA's Community Risk Assessment maps. Others license commercial catastrophe models such as CoreLogic Wildfire Risk Score or Verisk FireLine. What these systems have in common is that they all incorporate the same underlying physical factors: fuel load, slope-driven fire spread rate, ignition probability, and structure density. A property that scores "High" on HWMO will typically score in a similar tier on commercial models.
What Each Risk Tier Means in Practice
Low
Standard market coverage available from most carriers. Wildfire is not a primary underwriting concern. Premiums reflect the property's other risk factors (flood, wind, lava) rather than fire. Most of urban Honolulu, the wet windward sides of Oahu and Maui, and Hilo fall in this tier.
Moderate
Standard market coverage generally still available, but some carriers will apply a wildfire surcharge, require documentation of defensible space, or exclude wildfire from a standard HO-3 and require a separate endorsement. Properties at moderate elevations in leeward areas of Oahu (Ewa, Kapolei, Waianae), parts of Kihei and upcountry Maui, and dry-side residential neighborhoods on Hawaii Island fall here.
High
Standard market availability has tightened significantly for this tier since 2023. Properties scoring High are increasingly being pushed to the surplus lines market. Premiums for surplus lines wildfire coverage can be three to five times the standard market rate. Carriers may also require a higher deductible that applies specifically to wildfire losses, separate from the standard all-perils deductible. West Maui communities near Lahaina, Makawao-Pukalani, portions of the Kohala Coast, and Waimea on Hawaii Island are examples.
Very High / Extreme
Private market coverage for wildfire may simply not be available. The FAIR Plan (Hawaii Property Insurance Association) must accept the property, but FAIR Plan coverage is capped and more expensive than standard coverage. Some properties in this tier received non-renewal notices within 60 days of the Lahaina fire regardless of whether they had ever experienced a fire event. If you are in this tier, your broker's first job is finding surplus lines carriers that still write Hawaii wildfire; the FAIR Plan is the backstop, not the first call.
Which Islands and Areas Are Most Exposed
Maui County carries the highest aggregate wildfire underwriting risk because of the combination of dry leeward conditions, high population density in WUI zones, and the documented precedent of the 2023 Lahaina fire. West Maui from Lahaina north through Kapalua, the Central Maui corridor between Kahului and Wailuku, and upcountry communities from Makawao to Kula and Haiku are the most scrutinized areas.
Hawaii County (Big Island) has large dry-land areas on the leeward Kohala and Kona coasts where grass fire risk is well-documented. The Waimea plateau, Kohala Mountain Road area, and South Kona dry forests are the primary exposure zones. Properties in these areas that also carry lava hazard exposure face a compounding of two difficult underwriting problems simultaneously.
Oahu's wildfire exposure is concentrated on the dry leeward coast — Waianae Valley, Makakilo, and Ewa — and in the central plateau around Schofield. While Oahu's standard market remains more functional than Maui's, carriers have quietly tightened underwriting criteria in these areas since 2023. Kauai has wildfire exposure primarily in its dry south and west (Waimea Canyon area, Polihale), but the wet north and east coasts have no meaningful wildfire concern.
What Carriers Actually Look At When They Open Your File
The sequence a wildfire underwriter typically follows: (1) score the property address against their wildfire model, (2) check structure age and construction type — older wood-frame structures with wood shake roofs are the worst combination, (3) review defensible space — properties with vegetation trimmed to 30 feet and no wood decks attached to the structure score better, (4) check permit history for any recent roof work — a property with a permitted metal or Class-A asphalt roof within the last five years is treated materially differently than one with an unknown roof age.
If you know your HWMO score before you contact a broker, you can frame the conversation correctly. "The property scores Moderate on HWMO, has a 2021-permitted composition roof, concrete block construction, and cleared vegetation to 40 feet" gives an underwriter a reason to quote. Walking in blind with a High-score property and hoping the underwriter won't look is not a strategy.
Mitigation Steps That Actually Move the Needle
Not all mitigation steps are equal. The ones that underwriters consistently credit: (1) documented roof replacement with a Class-A fire-rated material — metal, concrete tile, or Class-A composition — in the last 10 years, (2) replacement of attached wood decks with composite or concrete, (3) installation of ember-resistant vents (conforming to ASTM E2886), (4) maintained defensible space of at least 30 feet with documentation. Carriers will sometimes offer a credit for properties enrolled in the HWMO Firewise program or with a formal home ignition zone assessment on file.
The key word is "documented." A carrier cannot credit a roof you replaced if there is no permit. A broker cannot argue for a rate reduction based on defensible space that you cannot show in photos with a timestamp. The documentation is the asset, not just the physical improvement.