How to Size a Trailer for Your Boat?

Having a boat trailer is a great thing, we can take our boat to different landscapes. The truth is that while there are many people who can recite a list of specifications for the craft, when choosing a boat trailer, there will still many questions. One of the most important is the issue of size.


For size selection, you can simply remember this thing: trailers are usually about 2 feet longer than the boat itself. Regarding length, LOA cannot be used as an indicator, because the trailer only supports the running surface of the hull’s running surface.

For width, trailers can usually only transport boats with beams smaller than 8’6″. Boats over this width usually cannot be transported on a trailer and may require an application.

Each boat trailer may have a large number of structural adjustments, and the axles may need to be moved in order to keep the tongue weight within the desired range of 5% to 7%. Most of the drawings you see are usually schematic and will not be drawn to a specific scale, but using these pictures will help you make a better choice of boat trailer size.

“A” Bow Eye to Transom Maximum
“B” Bow Eye to Transom Minimum
“C” Rear to Angle Support

boat trailer size
boat trailer size
boat size


The weight of a boat trailer is not calculated in the same way as other trailers, you cannot just calculate the empty weight of the boat. You also need to calculate fuel, water, batteries, gear, add-ons, etc. Typically fuel weighs 8.5 pounds per gallon and water weighs 6.5 pounds per gallon. If all the items together weigh less than 3,500 pounds, then you can choose a single-axle trailer. If the overall weight is over 3500 pounds, you will usually need to choose a tandem model.

Usually, if the total weight of the trailer exceeds 3,000 pounds, then you will need to install brakes on the trailer, as this is required by law. However, the law varies somewhat depending on the region, so you can decide whether to choose a trailer with brakes according to your local laws.

Other factors to consider


If your boat is fitted with a transducer, then you need to ensure that placing the trailer auxiliary bit does not come into contact with the transducer.

Bunks vs. Rollers

Bunks is used to provide support over the entire length of the boat. It is usually made of wood and covered with marine grade carpet. Rollers are easier to load and launch, but do not support the hull. Rollers may also cause hull denting. You can consult the boat manufacturer about your choice and they will usually give suitable advice.


Boat trailers usually have three types of frames: aluminum, steel, and galvanized.

  • Aluminum trailers are lighter and more resistant to corrosion, but less protective.
  • A steel trailer has a beautiful appearance because it will be painted for seawater insulation and corrosion resistance. But the paint would break over time, so galvanized trailers were invented.
  • Galvanized trailers are usually made by dipping the metal into a liquid zinc bath at 500°C, giving the metal a protective coating of silvery zinc. For saltwater boaters, galvanized boat trailers are the best choice.

If you want to buy a boat trailer, you can send us an email or send us a photo of your boat via WhatsApp and we will recommend a trailer for you based on your boat for your convenience.

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