How to Winterize a Boat For Storage
Sep 4, 2026 / Public Storage
How do you winterize a boat for storage?
Start by cleaning and drying the boat, draining water and fluids, preparing the engine, removing the battery, and covering the boat. Proper winterization helps protect your boat from freezing temperatures, moisture, corrosion, and mechanical damage while it’s stored.
Key Takeaways
- Clean and completely dry the boat before storage.
- Drain water from the bilge, tanks, plumbing, and engine as recommended by the manufacturer.
- Change the engine oil and filter and add fuel stabilizer.
- Remove the battery and store it according to the manufacturer’s instructions.
- Use a fitted, vented boat cover.
- Never run a boat engine inside a storage unit.
- Check your storage facility’s rules before bringing your boat or related equipment onsite.
- At Public Storage, items stored in a unit cannot be worth more than $5,000.
1. Clean and Dry Your Boat
Give your boat a thorough cleaning before putting it away. Wash the hull, clean compartments, and remove unnecessary gear and electronics.
Moisture can contribute to mildew and corrosion, so remove and dry cushions, rugs, life jackets, and other fabric items before storage.
You can also:
- Apply a marine-safe rust or corrosion inhibitor to appropriate metal components.
- Remove plants, barnacles, and other buildup from the stern drive.
- Inspect the hull and equipment for cracks, holes, or other damage.
- Wax the exterior for an added layer of protection.
- Use a mildew-control product inside the boat.
2. Drain Water and Fluids
Water left in a boat can freeze and potentially damage components. Drain water according to your boat manufacturer’s winterization instructions.
Depending on your boat, this may include:
- Draining the bilge.
- Emptying water tanks, manifolds, and coolers.
- Draining plumbing systems.
- Adding marine antifreeze to applicable sinks, showers, toilets, and other plumbing.
- Flushing and winterizing the engine according to the manufacturer’s instructions.
Because boats vary significantly, always follow the specific winterization procedure for your engine and boat model.
3. Prepare the Engine and Fuel System
Engine preparation is one of the most important parts of winterizing a boat.
Common steps include:
- Change the engine oil and oil filter.
- Replace the fuel filter if recommended.
- Fill the fuel tank and add the manufacturer-recommended fuel stabilizer.
- Run the engine briefly to circulate treated fuel only in a safe, well-ventilated outdoor area, not inside a storage unit.
- Fog the engine if recommended by the manufacturer.
If you’re unsure how to winterize the engine, consider having a marine technician perform the service.
4. Remove the Battery
Remove the boat battery before long-term storage and keep it in an appropriate cool, dry location. Follow the battery manufacturer’s charging and storage recommendations.
A battery maintainer can help keep a stored battery charged, but electrical equipment should not be operated inside a Public Storage unit unless specifically permitted by the facility.
5. Cover the Boat
Use a fitted, waterproof, and vented boat cover to help protect the boat from dust, moisture, and pests.
For additional moisture control, consider placing moisture absorbers inside the boat. Make sure the interior is dry before closing it up for the season.
Boat Storage Options
| Storage option | Best for | Key consideration |
| Indoor storage | Maximum protection from weather | Availability and unit dimensions |
| Covered storage | Added protection from sun and precipitation | Boat must still be properly covered |
| Outdoor storage | Convenient seasonal storage | Requires a quality cover and weather protection |
Before choosing a unit, measure the boat—including its trailer—and check the storage facility’s size requirements and policies.
Boat Winterization Checklist
Before storing your boat, make sure you have:
- ☐ Cleaned and dried the interior and exterior
- ☐ Removed cushions, rugs, gear, and unnecessary electronics
- ☐ Inspected the hull and equipment
- ☐ Drained water and winterized plumbing
- ☐ Serviced the engine
- ☐ Added fuel stabilizer
- ☐ Removed the battery
- ☐ Installed a fitted, vented cover
- ☐ Added moisture absorbers
- ☐ Confirmed your storage facility’s boat and equipment policies
FAQs
Do I need to winterize my boat before storage?
Yes. If your boat will be exposed to freezing temperatures or stored for an extended period, winterization can help protect its engine, plumbing, fuel system, and other components.
Can I run my boat engine inside a storage unit?
No. Never run a boat engine inside a storage unit. Engine exhaust can create dangerous carbon monoxide levels, and many facilities prohibit operating vehicles or engines inside units.
Should I drain my boat before winter storage?
Yes. Remove water from the bilge, plumbing, tanks, and other applicable systems according to your boat manufacturer’s instructions.
Should I remove the boat battery for winter storage?
Generally, yes. Removing the battery can help protect it during long-term storage. Store and maintain it according to the battery manufacturer’s recommendations and your storage facility’s rules.
What should I cover my boat with for winter?
Use a fitted, waterproof and vented boat cover designed for your boat. Proper ventilation helps reduce trapped moisture.
Can I store anything in my boat while it’s in a Public Storage unit?
Storage policies apply to both the unit and its contents. At Public Storage, nothing stored in a unit can be worth more than $5,000. Check your rental agreement and facility rules for additional restrictions before storing items inside your boat.
