A “Do Not Block” sign is a regulatory traffic sign that forbids you from entering an intersection, crosswalk, driveway, fire lane, or railroad crossing unless you can pass completely through without stopping. Under the federal Manual on Uniform Traffic Control Devices, the “Do Not Block Intersection” sign (code R10-7) sits in the same legal category as a stop sign or speed limit sign, so ignoring it is a citable offense.1Federal Highway Administration. MUTCD 2009 Edition Chapter 2B – Regulatory Signs, Barricades, and Gates Depending on where and how you violate it, the consequences range from a modest fine to a towed vehicle, points on your license, or, for commercial drivers, a federal disqualification.
What the Sign Actually Requires
The rule behind the sign is older and broader than the sign itself. Every state prohibits drivers from entering an intersection, marked crosswalk, or railroad crossing unless there is enough room on the other side to fit the vehicle without blocking cross traffic — regardless of what the signal shows. The sign gets posted where blocking has become a recurring problem, but the legal duty applies whether or not you see one.
A green light is permission to proceed if the space ahead is clear. It is not permission to enter a space you cannot exit. That distinction is the whole rule.
Where the Rule Applies
Intersections
“Blocking the box” is the most common violation. If traffic on the far side is backed up and you cannot clear the intersection before stopping, you have to wait behind the stop line, even on green. Entering on green and getting stranded when the light changes is still a violation, because cross-traffic now has a green signal and cannot move. Some cities paint yellow crosshatch grids inside the intersection to mark the zone, and a handful use automated cameras that mail citations to drivers photographed stopped in the box.
Crosswalks
Any part of your vehicle inside a crosswalk counts. Pedestrians forced around a stopped car often step into an adjacent travel lane with no warning to oncoming drivers. Both marked and unmarked crosswalks are covered — an unmarked crosswalk exists at every intersection where sidewalks meet the road, painted lines or not. The situation this catches most often is a right-turning driver creeping forward into the crosswalk while waiting for a gap.
Driveways
Stopping in front of a driveway, even briefly, even with hazards on, is a blocking violation almost everywhere. Private driveways and commercial driveways are both covered, and partial overlap counts: if any portion of your vehicle sits on the driveway apron, you can be ticketed or towed. The purpose is emergency access, not the property owner’s convenience, which is why in most places you can be cited for blocking your own driveway.
Fire Lanes and Hydrants
A red-painted curb or a “Fire Lane — No Parking” sign carries the same force as “Do Not Block.” The buffer around a fire hydrant is typically 15 feet in either direction so firefighters can connect hoses. These zones get towed aggressively, often within minutes of a report, and the fines run higher than ordinary parking tickets.
Railroad Crossings
Stopping on the tracks is one of the most serious traffic violations on the books. A train cannot swerve and needs a mile or more to stop. Every state treats stopping on a crossing as a moving violation, and many attach enhanced fines above what a standard intersection-blocking ticket would cost.
When the Train Is the One Blocking You
Drivers often assume the rule cuts both ways. It does not. There is no federal law limiting how long a train can block a public road crossing.2Federal Railroad Administration. Highway-Rail Grade Crossing Safety Roughly half the states have passed their own time limits — commonly five, ten, fifteen, or twenty minutes — but those laws face a serious preemption problem. Under 49 U.S.C. § 20106, federal railroad safety regulations require rules to be “nationally uniform to the extent practicable,” and railroads have successfully challenged many state and local blocked-crossing ordinances on that basis.3GovInfo. 49 USC 20106 – Preemption A state can add its own rule only if it addresses an “essentially local safety hazard,” does not conflict with federal law, and does not unreasonably burden interstate commerce. If a train has stopped across your route, the FRA operates a public incident reporter for logging it.4Federal Railroad Administration. Public Blocked Crossing Incident Reporter
Penalties
Fines and Surcharges
Base fines generally fall between $50 and $300, with intersection violations at the higher end and driveway violations sometimes lower. The surprise is the surcharges. State penalty assessments, court construction fees, and emergency services assessments stack on top of the base fine, and in some jurisdictions those add-ons multiply the printed amount several times over. A $35 base fine can arrive as a $230 total. Assume you will pay well above the number on the citation.
Points on Your License
Many states treat blocking an intersection as a moving violation and assign two or three points to your driving record. Enough points in a set window triggers driver improvement requirements or suspension. Points typically stay on your record for several years, so a run of small violations can add up faster than drivers expect.
Towing
A vehicle blocking a driveway, fire lane, or hydrant can be towed with no warning. Expect $150 to $300 or more for the tow itself, plus storage fees of $20 to $100 per day starting the moment the vehicle reaches the impound lot. In many jurisdictions you also have to pay the underlying ticket before the vehicle is released.
Commercial Drivers Face a Different Penalty
If you hold a CDL, blocking a railroad crossing is not just a fine. Federal regulations require a minimum 60-day disqualification from operating a commercial vehicle on a first offense, and that includes entering a crossing without enough space to clear it completely. A second conviction within three years carries at least 120 days, and a third within three years brings at least one year.5eCFR. 49 CFR 383.51 – Disqualification of Drivers Losing commercial driving privileges for 60 days is enough to cost most professional drivers their job.6Federal Motor Carrier Safety Administration. Highway Rail Grade Crossing – Safe Clearance
How to Avoid the Ticket
The habit that prevents almost every intersection and crossing violation is one step: before you enter, look past it. If the space on the far side is not clearly open enough to fit your whole vehicle, stay behind the stop line and wait. The green light is telling you the rule of right-of-way; the traffic ahead is telling you whether to move. When those two signals disagree, the traffic ahead wins.
At railroad crossings this caution is not about a ticket. It is about not being on the tracks when a train arrives that cannot stop for you.
For driveways and fire lanes, the fix is easier: do not treat them as temporary stops. “I’ll only be a minute” carries no weight with a parking officer or a tow operator, and the cost of circling the block is always lower than the cost of getting your car back from an impound lot.