Montana does not require boat insurance by law, but marinas, private launch facilities, and lenders make it effectively mandatory. If financed, your lender requires hull coverage. Marina contracts demand liability proof for slips/mooring. Your auto policy covers trailer liability on roads but drops once launched. With cold water, wind events, and remote locations, comprehensive coverage protects against liability claims and repair costs.

Agreed Value pays the full insured amount for total losses without depreciation-the value agreed at policy start. Actual Cash Value (ACV) pays depreciated market value at loss time, often much less than replacement cost. Agreed Value costs more but avoids post-loss disputes, ideal for customized boats, electronics upgrades, or financed vessels common on Montana lakes.

AIS prevention is a Montana FWP legal requirement, not directly tied to insurance eligibility. However, failing inspections prevents launching, and some carriers consider clean inspection history for discounts. Complete the online decontamination course and carry stickers. Violations can lead to fines and launch denials-both affect usability more than premiums directly.

Most Montana policies default to inland waters covering lakes, reservoirs, and navigable rivers. Confirm territory includes your full cruising area-Flathead to Fort Peck, Missouri River floats, or high-mountain lakes. Policies exclude ocean/coastal unless specified. We'll match limits to your trailer-towing range across FWP sites and private facilities statewide.

Not standard-towing/assistance and salvage require add-ons with separate limits. On-water towing handles fuel delivery, battery jumps, soft ungroundings, and marina tows. Salvage covers vessel recovery from deep water or rocky shores-critical for remote Montana reservoirs where costs skyrocket due to distance and terrain. Both essential given limited services in Big Sky Country.

Fuel spill liability covers cleanup costs and third-party damages from accidental fuel/oil discharges. Excluded from standard liability, it requires endorsement. Montana's pristine lakes and reservoirs demand protection-fines and remediation can exceed $100K even for small spills. Low-cost addition for any powered vessel operating in sensitive waters.

Limited coverage only. Homeowners may cover small boats as personal property with low limits, excluding watercraft liability. Auto covers trailer on-road but not water operation. For anything beyond a tiny rowboat, standalone boat insurance provides essential hull, liability, medical, towing, and gear protection tailored to Montana's unique exposures.

Lay-up periods reduce premiums for months when stored out of water/offline. Carriers require warranty against operation during lay-up-violation voids coverage. Match dates to your schedule: Flathead boats typically October-April. Too short overcharges; too long risks gaps. Some policies reimburse storage/haul-out for winterizing or hail events.