• October 20, 2025

Winter is Coming! It’s Time to Winterize Your Boat

As the boating season winds down, now is the time to start thinking about protecting your boat for the colder months ahead. Proper winterization protects your boat from cold weather damage and ensures a smooth, stress-free launch when spring arrives.

Winterization Basics

Boat U.S. provides a comprehensive playlist of videos, articles, and checklists to guide boat owners through the winterization process. Winterizing involves properly storing your boat, protecting the engines, and ensuring the plumbing is freeze-proof.

Start with Storage: Deciding where to store your boat is the first big decision.

  • Indoor storage offers the best protection, especially in climate-controlled facilities.
  • Outdoor storage on land works well if the boat is properly covered and supported with a cradle, trailer, or jack stands.
  • In-water storage is also an option but requires a few extra steps. Close all thru-hulls (except cockpit drains), secure dock lines, and check the boat periodically.

Drain Systems: Remove water from every part of the boat, including the sea strainer, engine blocks, plumbing systems, and air conditioning units. Add marine antifreeze to the bilge, keel, and water tanks to prevent freezing and cracking.

Prepare the Engine: Flush the engine with freshwater to remove salt, dirt, and corrosion. Refill the coolant system with antifreeze. If you choose to store your boat with a full fuel tank, add a fuel stabilizer and replace the fuel filters to prevent buildup and contamination.

Battery Maintenance: Disconnect and fully charge the battery. Store it in a warm, dry location until spring.

Clean and Remove Gear: Remove electronics, clothing, and safety gear. Clean the boat thoroughly to prevent mold and corrosion.

Since every boat is different, it’s important to check your owner’s manual for any specific instructions. Winterizing might take some effort, but these steps will help keep your boat in great shape and ready to hit the water when spring rolls around.

For more information or to contact our specialists, visit www.nmu.com.

 

This article is provided for general informational purposes only and does not constitute and is not intended to take the place of legal or risk management advice. Readers should consult their own legal counsel or other representatives for any such advice. Any and all third-party websites or sources referred to herein are for informational purposes only and are not affiliated with or endorsed by Intact Insurance Group USA LLC (“Intact”). Intact hereby disclaims any and all liability arising out of the information contained herein.

Intact Insurance Specialty Solutions, Intact Ocean Marine, and National Marine Underwriters are marketing brands for the insurance company subsidiaries of Intact Insurance Group USA LLC. Our solutions are backed by the financial strength of Atlantic Specialty Insurance Company, a subsidiary of Intact Financial Corporation (TSX:IFC), rated A.M. BEST A+ | FITCH AA | MOODY'S A1

Coverages may be underwritten by one of the following insurance companies: Atlantic Specialty Insurance Company, a New York insurer; Homeland Insurance Company of New York, a New York insurer; Homeland Insurance Company of Delaware, a Delaware insurer; OBI America Insurance Company, a Pennsylvania insurer; or OBI National Ins