Oversize Load Signs and Flags: A Simple Guide
Oversize Load Guide
Some loads just do not fit inside the lines. A wide tractor, a long steel beam, or a tall machine can hang past the edges of your trailer. Other drivers need to know that before they get close.
That is the job of oversize load signs. The bright yellow banner and the red flags tell everyone around you to give extra room. This guide explains when you need them, where they go, and what else you should carry.
One note before we start. Every state sets its own rules for big loads. Use this guide to learn the basics, then read the permit for every state on your route.
In This Guide
What Counts as an Oversize Load?
A load is oversize when it is bigger than the normal legal limits for the road. In most of the United States, those limits are close to these numbers:
| Measure | Typical Legal Limit |
|---|---|
| Width | 8 feet 6 inches |
| Height | About 13 feet 6 inches in many states, and a bit taller in some |
| Length | Changes by state and by the type of trailer |
| Weight | 80,000 pounds gross on most highways |
If your load goes past the legal limit in a state, you usually need a permit from that state. The permit lists the rules you must follow, including signs, flags, lights, travel times, and escort cars.
Overweight loads are a little different. A load can be too heavy without being too wide or long. Those loads need a permit too, but the sign rules may not be the same.
What Are Oversize Load Signs?
They are large banners or rigid signs that say OVERSIZE LOAD or WIDE LOAD. They are made to be read from far away.
In most states they share the same look:
- Bright yellow background
- Tall black letters
- About 7 feet wide and 18 inches tall
Some states ask for a certain letter height or a certain wording. Your permit will tell you which words to use.
Where Do the Signs Go?
Most states want one sign on the front of the truck and one on the back of the load or trailer.
Front. Mount it on the bumper or the front of the truck where it can be seen clearly.
Back. Mount it on the rear of the load or the trailer, as low and centered as you can while keeping it easy to read.
The sign must not cover your lights, turn signals, or license plate. It should be flat and tight, not folded or flapping.
When the big load comes off, take the signs down or cover them. Running with a sign when your load is a normal size can get you a ticket in some states.
Types of Signs
Vinyl Banners
These are the most common. They roll up small and weigh very little. Most have metal grommets along the edges so you can tie them on with rope or bungee cords.
Mesh Banners
Mesh banners have tiny holes that let wind pass through. They flap less at highway speed and put less pull on the tie points.
Rigid Signs
Some trucks use aluminum or plastic signs that bolt on or fold down from a bumper mount. They cost more but go up fast and stay flat.
Magnetic Signs
These stick to steel bumpers and doors. They are handy for pilot cars. Make sure the surface is clean so the magnet holds.
Warning Flags
Signs tell people a big load is coming. Flags show them just how big it is.
Flags are bright red or orange. A common size is 18 inches square, though some states allow smaller ones. They are placed at the points where the load sticks out the most.
Wide loads. Put a flag at each of the four corners of the load, and at any point that sticks out wider than the rest.
Long loads. Put flags at the very end of anything that hangs off the back. Many states require a flag when the load hangs 4 feet or more past the rear of the trailer.
Flags can be mounted on staffs, clipped to the load, or held with spring clips or magnets. They need to be able to wave freely so they catch the eye.
Lights
Flags work in daylight. At night or in bad weather, you need lights.
Many states ask for amber warning lights on the truck or on the widest parts of the load. Loads that hang off the back may need red lights at the end at night. Some states do not allow oversize travel after dark at all. Again, your permit has the details.
Escort Vehicles
Very wide, tall, or long loads may need an escort car, also called a pilot car. The escort drives in front, behind, or both. It warns other drivers and helps the truck through tight spots.
Escort cars carry their own signs and lights, and sometimes a height pole that checks bridges and wires ahead of a tall load.
A Checklist for Your Truck
If you haul big freight, keep this kit ready.
- Two banners, one for the front and one for the back
- A spare banner in case one tears
- At least six to eight red or orange flags
- Flag staffs, clips, or magnets
- Bungee cords or rope to mount the banners
- Amber warning lights if your routes need them
- A copy of every permit
- A tape measure to check your width, height, and length
You can find flags, banners, and other road safety items in the Safe & Tie safety equipment collection.
How to Mount a Banner So It Stays On
A banner that rips off on the highway is a hazard and a ticket.
- Use every grommet, not just the corners.
- Pull it tight so the wind cannot get behind it.
- Use rubber straps or bungee cords that can flex a little.
- Keep it away from hot exhaust.
- Check it at every stop.
Secure the Load Itself
Signs and flags warn people. They do not hold anything down. A big load puts more force on your tie downs, so plan for extra.
Use chains and binders for heavy machines and steel. Use straps and edge protectors for finished goods. Check that the total rating of your tie downs fits the weight of the load. You can find what you need in the cargo control collection and the chains and binders collection.
Common Mistakes
Assuming one state's rules work in the next state. Each state is different.
Using faded or torn banners. If it cannot be read, it does not count.
Covering lights or plates with the sign. Mount it lower or to the side.
Forgetting flags on the widest points. Corners alone may not be enough.
Leaving the sign up when empty. Take it down after delivery.
Not carrying the permit. Keep it in the cab where you can hand it over quickly.
Final Thoughts
Oversize load signs and flags are simple tools with a big job. They tell everyone on the road that your truck needs more space. Put a clear banner on the front and back, flag the widest and longest points, add lights when needed, and follow every line of your permit. Then tie the load down right, and you are ready to roll.
Get Your Oversize Kit in One Order
Two mesh oversize load banners plus four safety flags with dowels, bundled together.
Shop the Banner & Flag BundleFrequently Asked Questions
What size should an oversize load banner be?
A common size is about 7 feet wide and 18 inches tall with black letters on a yellow background. Check your state permit for the exact size it requires.
Do I need a sign for an overweight load?
Not always. Sign rules are mostly about size, not weight. Your permit will say if a sign is needed.
What color flags should I use?
Red or bright orange. Many states ask for flags that are 18 inches square.
Can I use a WIDE LOAD sign in place of an OVERSIZE LOAD sign?
Some states accept either one. Others ask for specific words. Read the permit for each state on your trip.
Do I need signs on both the front and the back?
In most states, yes. One goes on the front of the truck and one on the rear of the load or trailer.