Speed Regulations
Speed Laws, Rules & Regulations

Speed Regulations: Legal Speed Limits, Enforcement, Safety and Risks

Updated Oct. 20, 2020

When it comes to rules of the road, no traffic laws are more important than those governing the speed at which we can travel. Speed limit laws and regulations apply to every inch of public roadway in the United States. Driving is an inherently risky activity, both for the driver and every other person on or near the roadway. Speed limits are established to minimize this risk, with the aim of keeping all road users safe.

Most speed limits refer to the maximum speed at which a motorist may drive on that stretch of roadway. This is because the risk of being injured or causing injury generally increases the faster you are traveling. As speed increases:

  • Drivers have less control over their vehicles
  • Drivers have less time to react to hazards
  • A vehicle’s grip on the road’s surface lessens
  • A vehicle will cause more damage if a collision occurs
  • A vehicle’s total stopping distance increases

Every road in the United States has a maximum speed limit, whether it is posted on the actual roadway or simply written into state law. Comparatively, only very few roads have a minimum speed limit. The risk of a crash occurring usually decreases the slower a vehicle is traveling, except on certain high-speed roads where a vehicle driving significantly slower than other traffic would pose a hazard. On these roads, minimum speed limits usually apply.

Speed limits and driving risk

So, how are speed limits set? The maximum speed limit on a road reflects the potential hazards and level of risk associated with driving on that road. The more complicating factors there are, the lower the maximum speed limit is likely to be. For instance, most states set residential and business district speed limits at 30 mph or lower, as these areas generally have many risk-enhancing features, such as:

  1. 1

    Frequent intersections where drivers must stop, yield or turn

  2. 2

    A high volume of pedestrian traffic

  3. 3

    Many different types of road user. I.e. cars, trucks, buses, delivery vehicles, cyclists, motorcyclists

  4. 4

    A high number of distractions. I.e. road signs, traffic signals, advertisements, sidewalk activity, car horns

  5. 5

    Visibility limiting factors. I.e. trees, buildings, street furniture

At the other end of the scale, limited-access highways have no intersections, no pedestrian traffic, few distractions and great visibility. For this reason, these roads have the highest maximum speed limits in the country.

Whatever the speed limit on the road you are driving on, it is important to abide by it strictly. Failure to keep within set speed limits, or to adjust your speed when driving conditions are poor, places every person on the roadway in considerable danger.

Speed limit enforcement

The World Health Organization (WHO) identified speed control as one of the most essential intervention methods to help reduce traffic-related casualties around the globe. Detecting and deterring speeding drivers has become a matter of such importance that many states now permit the use of automated speed limit enforcement devices, such as speed cameras, to catch motorists breaking a speed limit. Presently, 13 states have passed laws that prohibit the use of speed cameras except under rare circumstances. The District of Columbia and 12 states currently have active speed cameras installed in at least one location.

Enforcing speed limits with speed camerasSpeed camera or a traffic enforcement camera may be used to control speed on stretches of the road where speeding is an issue.

Even in high-risk areas where automated speed enforcement devices are not used, traffic police officers are on the lookout for speeding motorists. Depending on the severity of the speeding violation and whether it was a first-time offense, drivers caught exceeding the speed limit may receive:

  • A fine.  Speeding fines vary considerably around the United States. In Ohio, speeders may be fined up to $150 for a first offense; $250 for a second offense and $500 for a third offense. Additional fines of $500 to $1000 will be added if injury or death is caused.
  • License points.
  • An order to attend a mandatory traffic school course.
  • A temporary suspension.
  • License revocation.
  • A term of imprisonment.  This is usually only applicable for second or third offenses or when the speeding violation results in injury or death of another person. However, some states may issue a short jail sentence for serious first-time offenses; usually, three to 10 days.

Choosing a safe speed

Choosing a safe speed at which to drive begins with identifying the speed limit for the road on which you are traveling – but it does not end there. Speed limits are based on ideal road, weather and traffic conditions. If any of these elements are not optimal, you will need to drive slower than the set speed limit to maintain safety. In the second article of this block, we discuss the various factors you must consider when selecting a safe driving speed. We also look at the consequences you may face, if you fail to choose a safe speed.

Speed limits across the United States

Next up, our course covers different speed limits and speed laws around the United States. As mentioned earlier, different areas and types of road have different “standard” speed limits. As these are individually set by each state government, they will vary around the United States. Plus, these standard or “prima facie” speed limits do not always apply. States have the power to set higher or lower speed limits by posting regulatory road signs, when the risk associated with a certain roadway demands it.

Our article features general guidelines for speed limits in different areas, though you must also refer to your driving manual for state-specific speed limits.

When to drive at reduced speeds

There will be many, many occasions where the situation requires you to drive slower than a maximum speed limit, or even a minimum speed limit. Exceeding a maximum speed limit is never necessary or permitted, though driving slower is often a legal obligation. No traffic law or traffic control device ever permits you to drive at an unsafe speed. If you are caught driving faster than is safe for current conditions, you will be cited for “driving at excessive speeds” “dangerous driving” or whichever traffic violation best suits your misdemeanor.

When driving in heavy traffic, bad weather, around children, at night, while towing another vehicle or when animals are nearby, motorists must reduce their speed. These issues are explored fully in this essential, final article.

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Choosing Safe Speed for Driving
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Choosing a Safe Speed

Motorists must choose a safe speed based on the posted speed limit, the speed of other vehicles around them and current driving conditions. Traveling faster gives you less time to see and react to hazards, makes maneuvering more difficult and means it will take longer for your vehicle to stop once the brakes have been applied.

Speed Limits Across the US
Speed Regulations 3 of 4

Speed Limits Across the US

Different states establish their own maximum and minimum speed limits based on these factors. The maximum speed limit on a rural expressway varies from 65 mph to 80 mph around America, with higher speed limits more commonly found in western states. Currently, the 85 mph is the highest speed limit in the country, which can be found in rural Texas on a limited stretch of tolled highway.

Driving Below the Posted Speed Limit
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Driving at Reduced Speeds

Adhering to a posted speed limit does not guarantee that you are traveling at a safe speed, nor does it always protect you from being cited for “driving at excessive speeds”. If any unfavorable driving conditions increase the likelihood of a crash occurring, or the probable severity of a crash, you must drive at a reduced speed.

Right of Way Rules 9 of 9

Right-of-Way at Railroad Crossings

Failure to observe proper right-of-way rules around railroad crossings can result in devastating collisions and loss of life. Trains always have right-of-way over road vehicles at railway crossings – there are no exceptions. As a motorist, you must yield the right-of-way or risk paying for the violation with your life.

Passing & Being Passed 1 of 3

Passing Others Safely

Passing another vehicle will always temporarily increase the risk you are exposed to at any given time on a stretch of roadway. Remember that most situations require passing on the left-hand side of the vehicle in front. Passing on the right is permitted only in certain rare circumstances.

Passing & Being Passed 2 of 3

When Passing is Legal

While on a two-way road with one lane of traffic moving in each direction, motorists may only pass another vehicle by merging left into the opposing lane of traffic. In most states, passing another vehicle on the right is prohibited except under certain conditions.

Passing & Being Passed 3 of 3

Allowing Others to Pass

In situations when another driver is seeking to pass you, consider what you can do to make the execution of that pass as easy as possible. Taking any steps to stop the driver from passing you is extremely dangerous and could cause a collision.

Stopping & Parking Responsibly 1 of 2

Choosing a Safe Parking Spot

Illegal or irresponsible parking can be just as disruptive and hazardous as bad driving! If you do not park properly, your vehicle may roll into moving traffic or pose a hazard to other drivers by obstructing important parts of the roadway.

Stopping & Parking Responsibly 2 of 2

Parking Prohibitions

Illegal parking can incur significant fines for the registered owner of the vehicle. If injury or property damage occur as a result of your improperly parked car, you can expect to be held financially responsible.