How to Choose the Right Size Boat Trailer

Why trailer size matters

The wrong trailer is more than an inconvenience — it can be dangerous. A trailer rated below your boat’s real weight strains the axles, tires, and brakes, and it can make highway handling unpredictable. Go too big, and the boat sits poorly on the bunks, which stresses the hull and makes launching and loading harder than it needs to be.

Getting the size right is mostly about honest numbers. Here is how to work them out.

Step 1: Know your boat’s loaded weight

The number that matters is not the brochure’s dry weight — it is the weight of everything that rides on the trailer: the hull, the motor (or motors), a full tank of fuel, batteries, and all your gear. Fuel alone adds roughly 6 pounds per gallon, so a 50-gallon tank is 300 pounds most people forget to count.

Add it all up, then add a safety margin of 10 to 15 percent. Your trailer’s carrying capacity should exceed that total, not just match it.

Step 2: Match the trailer length to the hull

The bunks or rollers should support the hull along most of its running surface, with the transom sitting at or just past the rear of the bunks. Too short and the stern hangs unsupported; too long and you are towing extra steel for nothing.

As a rule of thumb, the trailer is usually a couple of feet longer than the boat itself — but hull shape matters, so this is worth checking against the specific model, not just the length number.

Step 3: Pick the right axle count

Single-axle trailers suit lighter boats and are easier to manoeuvre by hand. Tandem axles (two) spread the load, tow straighter, and give you a margin of safety if one tire fails — most fishing boats in the 18 to 24-foot range belong on a tandem. Triple axles are for the heavy end of the scale, up to and beyond 10,000 pounds.

Step 4: Check your tow vehicle

Your truck or SUV has a maximum towing rating and a maximum tongue weight — both are in the owner’s manual. The loaded trailer must sit comfortably under both numbers. If you are close to the limit, a weight-distributing hitch is worth discussing.

When in doubt, ask someone who sizes trailers every day

If you tell us your boat’s make, model, motor, and how you use it, we will point you at the right Load Rite 5 Starr trailer the first time — no guesswork. Call Sportfishing Boat Sourcing at (778) 242-0460. We would rather talk you out of the wrong trailer than sell you one.