Yes, you can store a jet ski in a storage unit, but only if the unit is climate-controlled and large enough to hold it safely

A jet ski can go in a storage unit, but it requires more care than storing furniture or boxes. The main challenge is that jet skis are sensitive to temperature swings, moisture, and fuel breakdown. A standard unheated, uninsulated unit will damage the engine and fuel system over time. You need a climate-controlled unit — one that keeps temperature and humidity stable year-round — and enough floor space to position the ski without cramping it against walls or other items.

Most jet skis are 10 to 12 feet long, 4 to 5 feet wide, and weigh 600 to 1,200 pounds. A 10-by-10-foot unit is the practical minimum; a 10-by-15-foot unit gives you room to work around it and store related gear like covers, batteries, and fuel stabilizer. You'll also need to drain and prepare the ski before storing it, which takes a few hours but prevents thousands of dollars in engine damage.

Key Takeaways

  • Climate-controlled storage is essential because temperature swings and humidity cause rust, corrosion, and fuel breakdown inside the engine.
  • You must drain the fuel tank or add fuel stabilizer, flush the cooling system, and change the oil before storage to prevent internal damage.
  • A 10-by-10-foot climate-controlled unit is the minimum size; a 10-by-15-foot unit is safer and allows you to move around the ski.
  • Store the jet ski on a trailer or on jack stands to keep weight off the hull, and cover it with a breathable tarp to block dust without trapping moisture.
  • Check on the ski every two to three months and run the engine briefly every six months if you're storing it for longer than a season.

Why climate control matters for jet ski storage

Jet skis are built to live in water, not in temperature swings. When a storage unit heats up in summer and cools down in winter, the metal parts expand and contract, opening tiny gaps where moisture seeps in. That moisture sits on the engine, carburetor, and fuel injectors and turns to rust. The fuel itself breaks down in heat, turning into varnish that clogs the fuel lines and injectors — a repair that costs $300 to $800.

Humidity is equally damaging. A standard storage unit in a humid climate can reach 80 to 90 percent humidity, especially if the door opens and closes. That moisture condenses inside the engine block and fuel tank. Over six months, you can have corrosion on internal engine parts that won't show until you try to start the ski again.

A climate-controlled unit keeps temperature between 55 and 75 degrees Fahrenheit and humidity below 50 percent. This slows rust, prevents fuel breakdown, and keeps seals and gaskets from drying out and cracking. The cost is higher — typically $100 to $200 per month depending on your region — but it's far cheaper than an engine rebuild.

Preparing your jet ski before storage

The work you do before the unit door closes determines whether your ski starts in six months or needs an engine overhaul. Start by running the ski in fresh water for 10 to 15 minutes to flush out salt and debris from the cooling system. If you've been using it in saltwater, this step is critical.

Next, drain the fuel tank completely or add a fuel stabilizer to the tank and run the engine for 10 minutes to circulate it through the fuel lines and carburetor. Fuel stabilizer costs $8 to $15 per bottle and prevents varnish buildup. If you drain the tank instead, you'll also need to drain the carburetor by running the engine until it stalls, which uses up all fuel in the lines.

Change the oil and oil filter while the engine is still warm — old oil holds acids and moisture that corrode internal parts. Flush the cooling system with fresh water and add antifreeze rated for marine engines if you live in a freezing climate. Remove the battery and store it separately in a cool, dry place, or connect it to a battery tender that keeps it charged without overcharging. Finally, top off the gas tank (if you're keeping fuel in it) to prevent condensation from forming inside the tank.

Positioning and protecting the jet ski in storage

Never rest a jet ski on its hull for months at a time. The weight concentrates on a small area and can crack the fiberglass or warp the hull. Instead, place it on a jet ski trailer or on four jack stands positioned under the frame. If you use jack stands, place them under the reinforced areas near the engine and the rear, not under the hull itself. Check the stands every month to make sure they haven't shifted.

Cover the ski with a breathable tarp or cover designed for jet skis — not a plastic tarp that traps moisture underneath. Breathable covers let air circulate while blocking dust and light. find the cover loosely so air can flow, and leave small gaps at the bottom for ventilation. Remove the cover and wipe down the ski every two to three months to check for condensation or corrosion.

Store the battery, spark plugs, and any removable electronics in a separate, sealed container with desiccant packets to absorb moisture. Keep fuel stabilizer, oil, and maintenance records in a waterproof bag attached to the ski so you remember what you did and what comes next.

Size and layout of the storage unit

A 10-by-10-foot unit fits a jet ski, but barely. You'll have room for the ski and a narrow walkway on one side, but no room to move around it or store accessories. A 10-by-15-foot unit is more practical — it gives you space to position the ski, walk around it, and stack a few boxes of gear or maintenance supplies along the wall.

Position the ski toward the back of the unit so the door doesn't swing into it every time you open it. Leave at least two feet of clearance on all sides so air can circulate and you can inspect the hull and engine. If you're storing a trailer as well, measure the trailer length and width and add them to your calculation — a jet ski on a trailer can be 15 to 18 feet long.

Avoid units on the ground floor of a multi-story building if possible, because they're more prone to flooding and temperature swings. A second-floor or interior unit tends to have more stable temperature and lower flood risk. Ask the facility manager which units stay driest and warmest before you sign the lease.

Maintenance checks during storage

A jet ski in storage isn't truly dormant — it's slowly oxidizing and settling. Check on it every two to three months. Open the cover, look for condensation or corrosion on the engine, and wipe down any moisture you see. Check the battery if you're keeping it in the unit, and make sure the jack stands or trailer hasn't shifted.

If you're storing the ski for longer than six months, start the engine briefly every six months to circulate oil and fuel stabilizer through the system. Run it for five to ten minutes in a well-ventilated area (not inside the storage unit). This keeps seals from drying out and prevents fuel from settling and separating. Don't run it hard — just let it idle.

Before you take the ski out of storage, change the oil again, check the battery charge, and inspect the fuel system for any signs of leaking or corrosion. If the ski has been stored for a year or longer, consider having a marine mechanic do a pre-season inspection to catch any problems before you take it on the water.

Alternatives to storage units for jet skis

If a climate-controlled storage unit is too expensive or unavailable in your area, other options exist. A covered boat storage facility often has climate control and is designed for watercraft — it costs more per month but includes insurance and maintenance support. Some marinas offer indoor storage during the off-season, though availability varies by region and season.

A garage or shed on your property is ideal if you have one, because you control the environment and can check on the ski anytime. If your garage isn't insulated, add a space heater and a dehumidifier to keep temperature and humidity stable. A carport or canopy is better than nothing but won't protect against humidity or temperature swings the way a climate-controlled unit will.

Some owners keep their jet skis in the water year-round, moored at a dock or in a slip. This works in warm climates but requires regular winterization in cold climates and leaves the ski exposed to weather and theft. It's not a storage solution — it's a different way to own and use the ski.

Frequently Asked Questions

Can I store a jet ski in a regular (non-climate-controlled) storage unit?

You can, but you risk serious engine damage. Temperature swings cause rust and corrosion inside the engine, and fuel breaks down in heat. If you must use a regular unit, drain the fuel completely, add oil stabilizer, and check the ski every month. Even with these steps, expect problems after six months or longer.

How much does climate-controlled storage cost for a jet ski?

Climate-controlled storage typically costs $100 to $200 per month, depending on your region, the facility, and the unit size. A 10-by-10-foot unit is usually cheaper than a 10-by-15-foot unit. Call local facilities for exact pricing in your area.

Do I need to winterize a jet ski before storing it?

Yes, winterization is the same as the preparation steps described above: drain or stabilize fuel, change oil, flush the cooling system, and remove the battery. These steps prevent rust, corrosion, and fuel breakdown whether you're storing it for winter or for any other reason.

What happens if I don't drain the fuel before storage?

Fuel breaks down in heat and turns into varnish that clogs the carburetor, fuel injectors, and fuel lines. When you try to start the ski, it won't run, and cleaning the fuel system costs $300 to $800. Using fuel stabilizer prevents this, but draining the tank is the safest option.

Can I store a jet ski on its side?

No. Storing a jet ski on its side can damage the hull, crack the fiberglass, and cause oil to leak into the carburetor and cylinders. Always store it upright on a trailer or jack stands, or in the water if that's an option.