A Trusted Source For Boating Information Since 2019

Winterizing Your Boat

Boats in storage for winter

Disclaimer: You might notice that we recommend products in some articles. We may earn a commission for referring you if you click the link and buy a product.

We only recommend products we’ve tried/tested/own (that’s why you won’t find thousands of affiliate links on my site). If you have experience with one of the products we’ve mentioned, please share your experiences in the comments at the end.


Top-rated trolling motors on Amazon

If you live in a place where winters can be challenging, like I do, then you recognize when the air gets that familiar fall chill.  Protecting your valuable toys is important and so getting it ready for winter is crucial. Making sure you are thorough in the winterizing your boat process is the only thing that’s going to protect your investment from the frigid cold of winter.

General Procedures For Winterizing Your Boat

Before you run out and get yourself a mobile wrap appointment, there are a few other things to consider.  There are 5 aspects of your boat winterization that you want to focus on.

  1. Boat And Trailer Physical Storage Location
  2. Motor And Drive Assembly Preparation
  3. Electrical Systems Preparation
  4. Interior Preparation
  5. Hull & Exterior Preparation

Boat And Trailer Physical Storage Location

The best place for your boat for the winter is climate-controlled indoor storage.  This can cost a lot of money though. It is the best option, but if this cost isn’t in your boating budget then there are a few other things you can do.

Typical Storage Fees

Seasonal Outdoor Storage For Winter $ 4.40/sq ft

Therefore a 36’ boat at 10’ wide storage space = $1584


Top-rated fish finders on Amazon

Seasonal Indoor Heated Storage For Winter $ 11.25/sq ft

Therefore a 36’ boat at 10’ wide storage space = $ 4050

Motor And Drive Assembly Preparation

Yes, I’m sorry but a part of wintering your boat is working on the motor. There are several different types of boat propulsion, and each one has its own unique set of winterizing strategies and procedures.  Here are some general procedures to start with, for each different motor and propulsion type.


The fuel is a relatively easy process to make sure it’s good for winter.  Simply fill up your tanks with fresh gas. Add a gas stabilizer (gas line antifreeze included).  Change your fuel filter or filters and also any water separation filters. That’s all really.  

If you have a small boat and you use any kind of portable fuel tank, it’s best to move it somewhere safer for storage after emptying it.  Dispose of any gas according to local legislation, and store your tank in your yard shed or similar location.

Inboard Engine

Like any fuel-burning engine where the oil is separated from the gas, there’s going to be sludge.  Boat engines are notorious for having sludge build-up. The older ones at least. Even if you have a newer engine, it’s likely a good practice to change the oil when the engine is warm.  You have to use caution not to burn yourself in case it’s moved from the realm of warm to hot though. But the benefit outways the risk, in my personal opinion anyway.

So, you change the oil when its warm to give a better chance of getting the impurities inside to flow out with the warm, easy flowing oil.  If the oil were cold, then it’s going to creep out and cold sludgy impurities could remain in the engine. Best practice, warm up the engine, change the oil and put in some good quality oil with a new oil filter for the winter.


Top-rated boat gps on Amazon

Cooling System Prep

Depending on what type of cooling system your engine is set up with, another step in winterizing an inboard engine is to circulate antifreeze through the manifold.  If it’s a raw water cooling system, you just have to attach the inlet hose line to a hose and stick it in a bucket of the manufacturers’ recommended type of antifreeze.  Cycle it into the system as per the manufacturers’ specific procedures and that’s that, as they say.

Check that your engine is dry and clean, a little light oil like wd-40 on a shop rag and give it a wipe down.  That will help prevent surface rust from forming over the winter months.

Also take a look at your transmission.  Changing the oil here is also a good practice concept.  This will depend on the model though as some are more difficult than others.  Newer models may not need you to do this, consult your owners manual for specifics to your boat model.

Removing spark plugs and giving a light spray with a light oil (see what your manual recommends) is a step some say is good to do.  I don’t bother though. I leave the spark plugs alone and in the spring when I get everything running again I put fresh plugs in any way, so I don’t bother pulling them at this point.

Outboard Engine

Outboards are fairly straight forward to winterize.  Consult the particular users manual for the particular model you have to be sure you do everything right.  Especially when it comes to draining the fuel properly. For Instance, I’ve got a basic list of general instructions that work for most outboards.

First, run the engine and flush with clean water.  Just hook it up to the water cooling inlet.  

Second, let all the water drain completely.  It’s at this point I usually give my engine a wipe down or even wash it with mild soap and water.  A thorough rinse is required if using any detergents like soap.  


Top-rated boat seats on Amazon

Next, disconnect the fuel line and run the engine until it runs out of gas.

Type Specific Step

The following step will really depend upon the particular style of engine you have but usually, you would apply a special oil spray to the engine pistons and various other components to prevent rust and corrosion and so on over the winter months.  Best to consult your owners manual for the particulars there. But again, this is a general set of instructions, not specific to your particular engine as I have no idea what you have. (P.S. tell me in a comment and I’ll write you a winterizing instruction for it, how’s that?)

Using a marine-grade grease, lubricate components such as the propeller shaft and gears.  Also, make sure you change any and all oil in the engine. Never leave an engine over the winter months with dirty old oil in it.  It will separate over time and leave the heavy gunk in all the lower areas of your engine. Best to change the oil when the motor is freshly run and still warm too.  Warm oil flows much better than cool oil and so you’ll be able to drain more of the old dirty oil if it’s warm, leaving less gunk behind to sit inside for the winter. This is an essential component to properly winterizing your boat so don’t skip these steps.

Stern Drive

With any stern drive propulsion system, there are a few things that make sense to do, no matter which model you have.  First, you’ll want to do the obvious. Clean off any barnacles or plants that are growing on or entangled on the drive assemblies lower units.  Next, you’re going to want to check the gear case and make sure you don’t have an excessive amount of water with the oil. That could be a sign that repair is required.  One of your seals may need to be replaced if there’s too much water. Usually, you might see a small amount, but again it’s kind of on a boat by boat basis. Older boats, more water in the gear case.  Newer boat, new technology, less mix of oil and water unless a seal has gone.

Depending on your particular boat, you may need to check hydraulic pumps, oil amounts and so on for lifts or hydraulic steering.  Again, it depends on your particular boat and you should always check your particular owner’s manuals for specific instructions, locations of gaskets and seals and of course the manufacturers recommended types of greases, oils, and lubricants.

Electrical Systems Preparation

The electrics of a boat are usually pretty straight forward.  But that isn’t to say that winterizing a boat doesn’t include a few things for the electrical. There are only really a few things that need to be addressed for most boats going into storage.  Here’s a basic 4 step program I use for winterizing electrical. Follow these steps:

  1. Check onboard for any and all electronic devices.  Remove any which are removable for storage separately for the winter.  
  2. Any electronic devices which use batteries, such as a GPS or fishfinder, or even a spare flashlight kept on the boat, should have the batteries removed.  Batteries have a tendency to not do well freezing and sitting for months. They can leak and cause damage to your electronics.  Remember to dispose of them safely, in accordance with local legislation.
  3. Remove the boat battery from the boat and store it separately.  I like to store my batteries in my basement for the winter. Unless its a battery designed for the cold of winter, it should not be left outside where it could possibly freeze.  Keep your marine battery indoors, in a dry place over the winter and it will greatly prolong the life of the battery. Just make sure to give it a charge every month or so to make sure it stays good over the dormant months.
  4. Ensure all boat wiring is secure and ideally covered with some sort of protective shielding or housing.  Best keep any loose wires secured and out of nibbling rodents reach. Never underestimate a mouse who wants to chew through your boat wiring.

Boat Interior Preparation

The boat interior preparation actually has a few different things which you’re going to want to pay attention to.


Top-rated boat bumpers on Amazon
  1. Bilges
  2. Fresh Water System
  3. Head
  4. Interior Quarters


You’ll want to make sure your bilges are clean and dry.  Give them a good cleaning with a decent brush and some weak soap and water.  Using something like mild dish soap with warm water will usually suffice.

After you’ve cleaned them out and rinsed them, give them a spray with a light oil that displaces water.  It doesn’t hurt to put a bit of antifreeze in there either, just in case there’s some water sneaking around that you missed.

Fresh Water System

The freshwater system will need to be completely drained as a part of winterizing your boat.  Assuming your watercraft is smaller than 100 feet long and you likely don’t have an onboard heating system that you run year-round.  Wouldn’t that be nice though?  

Anyway, back to the point, and that is that you must make sure all water is out of the system.  Then you pump in antifreeze. Make sure you have all the faucets and so on open. Don’t stop pumping in antifreeze until it comes out the faucets.  Check with your boat manual to make sure you use the right kind of antifreeze. It has to be safe to use in your water supply. Assuming again, that your water on your vessel is drinkable.  

Typically you would also want to isolate the hot water tank.  You do this by filling it with antifreeze and connecting its intake line into the output line.  This closes the liquid circuit unto itself. Again, make sure you use the correct type of sale antifreeze in the tank.  And again, I must recommend you consult your owners manual for the specific procedures recommended for your individual craft.  But those are the basic instructions, so you get the idea.


Have you ever heard that old expression ‘gotta go hit the head’?  Well, in case you weren’t aware, this is your sewage containment system.  And yes, it’s something that has to be dealt with as a part of winterizing your boat. Make sure you pump it out at an approved facility. Then, fill the bowl with water and flush, do this several times while pumping out the system.  This will flush it.  

Follow your user manual though for proper winterizing procedures for your particular boat.  Often it will be recommended that you pump antifreeze into the system, sometimes alcohol-based, sometimes not.  Your user manual for the particular system in your boat will say what is needed but this is definitely not a step you want to skip.


Top-rated boat anchors on Amazon

Interior Quarters

If you have a kitchen, refrigerator, counters, drawers, storage areas or upholstery, then now is the time to get them ready.  Clean all as required, especially any areas that may have had food or fish guts, or anything that might leave behind something that could rot. This part of winterizing your boat is easy and straight forward I think.

Clean any areas you may have kept fishing supplies, or the washroom if the boat is equipped with one.  The idea is to give the whole thing a really thorough cleaning to eliminate mold and bacteria. Sanitize the interior as best you can.  

For upholstery, cushions, that sort of thing, ideally you want to remove them from the boat and store indoors in a climate-controlled area.  But, if it is fixed upholstery, make sure it is clean and dry. If it is a large boat, you may want to install a dehumidifier with a drain line that automatically discharges out of the boat.  Or, if it’s a smaller boat, you can use one of the many products that help control moisture like the ones on the recommendations page.

And remember to remove any other valuables from the boat.  It’s a good idea to also remove any flares, fire extinguishers, PFDs, and lifejackets in order to do annual maintenance on all of them and keep them safe for the season in controlled conditions.  

Boat Exterior Preparation

In-Water Storage

Leaving the boat at the marina or dock?  Well, there’s still some work that’ll have to be done to prepare things for the winter to come.  

  1. Check the rudder shafts and stuffing boxes for leaks and fix accordingly
  2. Ensure all valves, inlets, seacocks and so on are closed, leak-free and secure
  3. Ensure your battery has a full charge and is topped up with water.  Test that your charging system is working to ensure no emergencies with failed bilge pump due to lack of power.
  4. Test all boat bilge systems to make sure that all floats work, that all pumps are functioning and that the system is performing as expected.  Make sure all float switches are free of debris and are functioning properly.  
  5. Lubricate any and all components as necessary to prevent corrosion over the winter months.
  6. If there is an actual possibility of freezing waters, make sure you have a bubbling system or a de-icing device to make sure the hull is not damaged by the expansion pressure of freezing water/ice.

Land Storage

When you pull your boat from the water, it’s always a good time to give the outside hull a once over.  Inspect the hull for any cracks in the seal, damage or points of corrosion or wear which need to be addressed.  

Clean the hull thoroughly and remove any barnacles that have attached themselves.  Make sure you get them all to give the hull a good cleaning. Now is a good time to give the hull a wax (after any minor repairs) to help keep it from deteriorating over the winter months.  

Pro Tip – Journal

A good practice is to keep a journal for your boat and trailer, and do annual visual inspections and keep good notes.  Its smart to document wintering your boat. Not only does such a practice increase not only the resale value but it also allows for two different benefits.  

First, should you decide you want to sell the boat or trailer, it will be an easy sell with having a journal of repairs and inspections.  Why? Because almost nobody does that. I can’t remember the last time I heard that someone bought a used car and actually got the complete history of the vehicle with it.  Usually, you don’t get that kind of insight. So, if you were selling, it would be an excellent selling feature to have that information.


Top-rated boat covers on Amazon
Why Not Track It All?

Second, tracking your boat, trailer and any other vehicle for that matter, is a smart idea.  It can help you to prevent certain repairs from becoming big problems by allowing you to track issues and prevent further damage.  Most people wait until something breaks before they fix it. But, if you had an idea that something was on the way out, you could prepare and make the process easier and maybe even cheaper.

After you’ve done the once over of the hull and any minor repairs that may need to be done, it’s time to seal things up.  That is, assuming you’ve taken care of everything else at this point. One of the easiest ways to keep your boat in good order over the winter is to tarp or shrink-wrap the boat.  If you’ve prepared the interior, getting it shrink-wrapped is an excellent option over tarping.  

Tarp Or Shrink Wrap?

Tarping Your Boat

If you want to save some money, then having a decent reusable tarp to cover your boat for the winter may be a decent option for you.  It has its pros and cons and these should, of course, be considered. Winterizing your boat coat can be difficult given the choices.

The positive side of a reusable tarp is that it is going to be the cheapest option for winterization.  Boats can cost a decent amount of money for land usage for storage purposes, so saving some money on covering the boat may just be what you need to do.  

The negative side of using a tarp is that the seal of a tarp is not going to be as good as that of shrink wrap.  Wrap clings right to the hull whereas a tarp needs to be tied down to it. Tarps will not stop mice and other rodents.  Not that shrink wrap will stop a determined rodent, we all know that, but it sure works well to deter them. The only issue I’ve seen with using shrink wrap is that when people wrap a moist boat then they get mold.  Improper preparation can cause shrink wrap to cause more harm than good. But tarps are not great at preventive harm in the form of wildlife. 

Shrink Wrap

The next best option for your boat is to have it shrink-wrapped.  The cost is variable, depending on where you are and how much competition there is for the service.  In my area, the cost to have someone come out and shrink wrap a boat range from $15-$25/linear foot length of the boat.  I live in Ontario, Canada so, those are Canadian dollars.  

Most companies that offer the shrink wrap service also offer a variety of additional upsell options like adding in a zippered door to the shrink wrap, or a pre-wrap anti-mold spray down.  There are other options too like getting a vent in the wrap which will allow for air exchange to help prevent any mold growth.

The best thing to do, if possible, is to have your boat out of the water and on land for the winter.  And allow it to thoroughly dry out before applying the wrapping process. If you shrink wrap a damp boat, you’re asking to uncover nasty mold in the spring when you unwrap the boat.  

Unwrapping In Spring

Speaking of unwrapping, I also found that around Southern Ontario (Canada) the going rate for the same companies who wrap the boats to come and unwrap is about $2/linear foot.  Pretty cheap, but they must have some kind of added on costs because if it were a 30’ boat, you pay them $60 to unwrap it. Most people who have owned or own a business will tell you, you can’t do a service call for $60.  Not if you want to stay in business anyway. So, I called around and most places around here have a $100 minimum call charge for mobile service. Some had environmental and truck charges they included. In short, nearly any way you slice it, you’re paying someone at least $100 to remove the wrap.  I’d probably rather buy a good pair of cutting scissors for the wrap and remove it myself.

More From Boating Guide Magazine

Return To Home * About Boating Guide * About The Author

Oh, and if you like boating with your dog, don’t forget to check out our friends at Dog House Times.


Top-rated boat lights on Amazon



Top-rated kayak accessories on Amazon

Share this post with your friends

Subscribe to our Newsletter

Join us in our love for all things water. And Adventure.

A boat drops anchor in a cove.

Everything You Need To Know About Boat Anchors (A Quick Read)

Most people enjoy being on boats. The smell of the water, the feel of the wind in your hair, and being around people you enjoy. It can make for a fun day. But at the end of the day, when you pull the boat back to shore, you will have to make sure that your boat stays in place. This is the job of the boat anchor.

Read More »
snow damage kayak

Can Snow Damage A Kayak

Advertisement Asking ‘Can snow damage a kayak?’ is a good idea when selecting a location for kayak winter storage. However, kayak outside storage for winter may not be the best solution, at least not for your kayak’s hull integrity. Snow can cause significant damage to your kayak. However, it is not just snow that can

Read More »
A man works on re-painting his boat hull.

An Easy Boat Repair Guide To Painting Over Gelcoat

Advertisement A Boat Repair Guide To Painting Over Gelcoat (aka Gel Coat) Paint is an essential part of boat repair, enhancing the overall look and helping seal the hull. Painting over the gel coat is good because the gelcoat acts as an adhesive for the paint to stay in the place. However, you will have

Read More »
Bowrider vs bass boat explained at Boating.Guide.

Bass Boats Vs. Bowriders (A Guide For New Buyers)

Advertisement Bass Boats Vs. Bowriders (A Guide For New Buyers) – A Boating Guide Buyer’s Guide Report for 2023. Are you curious to know the difference between bass and bowriders boats? While the two types of boats look similar in some ways, they are best suited for different purposes.  Bass boats are specifically designed for

Read More »
Who Makes Each Brand of Catamaran and Where They’re Built by Boating.guide

Who Makes Each Brand of Catamaran and Where They’re Built

Advertisement Boating Guide Presents: Who Makes Each Brand of Catamaran and Where They’re Built. Catamarans are gaining popularity among seasoned sailors. Their speed and reliability made them the top choice for family cruises and long distances voyages. Let’s dig deeper into their fabrication, shall we? Among the acclaimed Catamaran brands is Lagoon, Privilege, Gemini, Bali,

Read More »
A pile of tires is shown in this photo.

Boat Trailer Tire Guide

Advertisement A boat trailer tire is something that is neglected by most everyday people. In other words, a tire is an underrated part. However, the main question arises that is a tire underrated, or is it just a myth? This section deals with the factors and facts that are related to the boat trailer tire.

Read More »
Scroll to Top