Boat & RV Winterization Checklist

You should winterize your boat or RV before the first freeze in your area — typically between late September and early November. In northern states (Minnesota, Wisconsin, Michigan), aim for mid-October. In mid-Atlantic and southern states, late November to early December is usually safe. The key is to complete winterization before temperatures consistently drop below 32°F (0°C), as frozen water in engines, pipes, and tanks can cause thousands of dollars in damage.

Most boat and RV owners can handle winterization themselves with basic tools, non-toxic antifreeze, fogging oil, and a fuel stabilizer — total cost is typically $50–$100 in supplies. However, if you have a complex inboard engine, generator, or hydraulic systems, hiring a professional ($150–$300 for boats, $100–$200 for RVs) ensures nothing is missed. Many storage facilities offer winterization services as an add-on — ask when booking your winter storage.

Failing to winterize can lead to expensive damage: frozen water expands and can crack engine blocks ($2,000–$8,000 to replace), burst water lines ($500–$2,000 in repairs), and damage water heaters and pumps. Unstabilized fuel degrades and gums up carburetors and fuel injectors. Batteries left connected will fully discharge and may not recover. Mold and mildew can ruin upholstery and cabinetry. Proper winterization takes 2–4 hours but can save thousands in spring repair bills.