Yes, you can drive with your trunk open in most states, but only when you’re actually transporting something that won’t fit with the lid closed, and only if you manage the visibility and safety problems the open lid creates. A small number of states cite drivers for an unsecured trunk, tailgate, or hatch even when nothing is inside. Everywhere else, the open trunk itself isn’t the violation; what gets drivers ticketed is an obscured license plate, a blocked tail light, an unflagged load, or cargo that shifts or falls out.
When It’s Legal and When It Isn’t
Every state allows you to haul bulky items that extend past the trunk line, as long as the cargo is properly secured. The open lid has to serve a purpose. Lumber, furniture, a bicycle, a mattress — anything genuinely too long or wide to fit inside is fair game. Driving around with the lid up and nothing in the trunk, or with items small enough to close the lid over, is where some jurisdictions draw the line and write a ticket.
A common misconception is that federal law caps how far your cargo can stick out the back of a passenger car. The three-foot front and four-foot rear figures people cite come from federal regulations covering commercial carriers on the National Network, not personal vehicles.1eCFR. 23 CFR Part 658 – Truck Size and Weight, Route Designations – Length, Width and Weight Limitations For your car, SUV, or pickup, the overhang limit comes from your state’s vehicle code. Some states allow ten or fifteen feet of rear overhang on certain roads; others cap it at three or four. Check before you load.
Flagging Cargo That Sticks Out
Nearly every state requires a bright flag on cargo that extends past the rear bumper, with the usual trigger being a load that protrudes four feet or more. Thresholds vary, so verify your state’s number. The flag typically has to be at least twelve inches square and visible from behind. At night, a red light or reflector is required in place of or in addition to the flag.
The reason is simple: a driver behind you has no depth cue for where your load actually ends. A long plank jutting from a trunk is nearly invisible in low light, and failing to flag it is one of the most common citations officers write during enforcement stops.
Keeping the Plate, Tail Lights, and Signals Visible
A raised trunk lid almost always blocks something an officer can see from behind — your rear license plate, one or both tail lights, your brake lights, or your turn signals. Every state requires the plate to be readable and the rear lights to be unobstructed while the vehicle is moving. The officer doesn’t need to evaluate your cargo to pull you over; a covered plate or a blocked brake light is the violation.
Two practical fixes handle this. For the plate, move it temporarily to a visible spot on the cargo or bumper, or mount it to a flag that keeps it readable. For the lights, aftermarket magnetic LED tail lights can be clipped to the cargo or to the edge of the trunk itself. They run under twenty dollars at most auto parts stores and are worth keeping in the car if you haul bulky items with any regularity.
Securing the Load
Choosing Tie-Downs
Ratchet straps are the most reliable option for heavy or awkward loads. Each strap has a working load limit printed on the label, which is the maximum weight it’s designed to hold during transport. Exceed that number and the strap can snap. Bungee cords are acceptable for light items but stretch over bumps and lose tension. Rope is a last resort and only works if you know a knot that won’t slip under vibration.
A good baseline: at least one tie-down for small, light loads under about five feet, a second for anything heavier or longer, and another for every additional ten feet of cargo length. Those numbers mirror federal securement rules for commercial vehicles and translate well to personal use.2eCFR. 49 CFR 393.100 – Applicability and General Requirements of Cargo Securement Standards
Stabilizing the Load Inside the Trunk
Tie-downs keep cargo from flying out, but they don’t stop it from sliding around. Anti-slip matting under the load reduces movement, and blankets or soft bags filling the gaps keep items from shifting side to side. Bundle similar items together before strapping. One tight bundle is easier to secure than four loose pieces.
Controlling the Trunk Lid
The lid itself needs to be held at a stable angle. Left to bounce freely, it stresses the hinges and creates unpredictable movement that loosens everything else. Run a bungee cord or short strap between the lid and the bumper, or anchor it to the cargo. Not so tight that it presses the load forward, just tight enough that wind and road vibration can’t whip it around.
Hazards to Know Before You Pull Out
Carbon Monoxide in the Cabin
This is the risk most drivers underestimate. SUVs, hatchbacks, and minivans are especially prone to pulling exhaust fumes into the cabin when the rear is open, because of the low-pressure zone that forms behind the vehicle at speed.3Centers for Disease Control and Prevention. Carbon Monoxide Poisoning Basics Carbon monoxide is odorless, and symptoms like headache, dizziness, and confusion can set in before you notice. If you must drive with the rear open, set your climate control to fresh air, run the fan on high, and crack the front windows to maintain positive airflow through the cabin.
Lost Rear Visibility
A raised trunk lid blocks the interior rearview mirror on most sedans entirely. You’re left with side mirrors only, which cuts out your view of anything directly behind you. Manageable on surface streets, riskier on highways where lane changes depend on that wider field of view.
Compromised Backup Camera and Blind-Spot Sensors
Vehicles made after May 2018 are required to include rearview backup cameras meeting federal field-of-view standards.4eCFR. 49 CFR 571.111 – Standard No. 111; Rear Visibility Those standards assume the trunk is closed and latched. With the lid up, the camera often points at the underside of the lid, which makes it useless when you’re backing out of a parking space.
Blind-spot monitors use radar sensors near the rear bumper corners. Protruding cargo or a raised lid can block or deflect those sensors, producing false alerts or silently disabling the system. Some vehicles warn you when the system is down; not all do. Assume the rear-facing electronics are compromised whenever you drive with the trunk open, and check mirrors manually.
What a Ticket or Accident Can Cost You
An unsecured load that doesn’t cause an accident usually ends with a traffic citation. Fines across the fifty states run from $10 to $5,000, with the wide range reflecting the gap between a minor first offense and a repeat violation or an obviously hazardous load.5U.S. GAO. Hazardous Driving: Unsecured Loads on Our Roadways Some states also assess points against your driving record.
Penalties climb fast once the load causes damage or injury. At least fifteen states treat unsecured load violations as misdemeanors carrying potential jail time, and the most serious cases involving substantial bodily harm or death can bring gross misdemeanor or felony charges, with up to a year in jail and fines reaching $5,000.5U.S. GAO. Hazardous Driving: Unsecured Loads on Our Roadways Several states have specific statutes making it a crime to cause injury through failure to secure cargo.
Then there’s civil liability. If your cargo damages another vehicle or injures someone, that driver’s insurer will pursue yours, and anything your liability coverage doesn’t pay comes out of your pocket. The negligence bar is low when a witness or dashcam shows the item falling from your open trunk.
Quick Pre-Drive Check
Before you pull away, walk around the back of the car and confirm three things: your license plate is readable, your rear lights aren’t blocked, and the load sits within your state’s overhang limit. If anything extends past the bumper, flag it in daylight or light it at night. Then pull over after the first mile to re-check strap tension. Loads settle, straps loosen, and the first few minutes of driving are when you’ll catch a problem before it becomes a hazard.