Written and reviewed by Tarihya J. McClain, Managing Attorney
Last reviewed: August 19, 2026
Missouri SB 1408 takes effect August 28, 2026, increasing the state’s uniform maximum speed limit from 70 to 75 miles per hour on rural interstates and qualifying freeways. But the most important rule for Missouri drivers remains simple: follow the speed-limit sign in front of you.
The new law does not make 75 mph legal on every interstate or highway. It applies only to certain road classifications, and transportation authorities may establish a lower limit for a particular location.
What changes under Missouri SB 1408?
Beginning August 28, Missouri SB 1408 permits a maximum speed limit of 75 mph on rural interstates and qualifying freeways.
However:
- The change applies only to qualifying roads.
- The Missouri Highways and Transportation Commission may establish a lower limit when appropriate.
- Urban interstate limits are not automatically increased to 75 mph.
- Rural expressways remain subject to a different statutory limit.
- The posted speed-limit sign remains the safest and most reliable instruction for drivers.
If the sign says 70, drive 70 or below—even if another section of the same interstate has been posted at 75.
Where can the 75-mph limit apply?
The new maximum applies to two categories of road.
Rural interstates
A rural interstate is the portion of the federal interstate system that is not located in an urbanized area. The same interstate may therefore have different limits as it passes through rural and urban locations.
Qualifying freeways
Missouri law defines a freeway as a limited-access divided highway that:
- Is at least ten miles long;
- Has four or more lanes;
- Is not part of the federal interstate system; and
- Has no same-grade crossovers or access points from other roads within that ten-mile stretch.
Drivers should not try to determine from memory whether a road satisfies every part of that definition. Look for the posted limit.
Where does the law not automatically raise the speed limit?
Missouri SB 1408 does not make 75 mph the statewide speed limit. The final bill leaves the uniform limits for several other road types unchanged, including:
- Rural expressways, which remain at 65 mph under the statute;
- Interstates, freeways, and expressways within urbanized areas, which remain at 60 mph under the uniform statutory provision;
- Other rural roads, which remain subject to their existing classifications and limits; and
- Lettered state roads, which remain governed by separate provisions.
The transportation commission and certain local authorities may establish lower limits when authorized. Posted signs may therefore differ from the maximum permitted for a road category.
Why posted speed-limit signs still matter
Missouri SB 1408 states that, for enforcement purposes, the posted speed limit is presumed to be the legal speed limit.
The law also allows the transportation commission to set a limit higher or lower than the uniform maximum when recommended by the Missouri Department of Transportation, as long as no limit exceeds 75 mph under this provision.
Practically speaking, drivers should not accelerate to 75 simply because August 28 has arrived. Wait until the road is actually posted for 75 mph.
What happens if I exceed the posted speed limit?
SB 1408 retains the penalty structure within Section 304.010:
- A violation is generally classified as a Class C misdemeanor.
- Exceeding the posted speed limit by 20 mph or more is classified as a Class B misdemeanor under this section.
A speeding conviction may also affect a driver’s record, points, insurance, employment, or commercial driving privileges depending on the charge and individual circumstances. If you received a citation, review McClain Law’s guidance on Missouri traffic-ticket defense before deciding how to respond.
The outcome of a traffic case is never guaranteed. The court, jurisdiction, driving history, alleged speed, and evidence all matter.
What should I do after receiving a Missouri speeding ticket?
Do not assume that paying the ticket is the only option—or that payment has no consequences. Paying a ticket generally resolves it as a conviction to the charged offense.
- Read the ticket and confirm the court, appearance date, alleged speed, and posted limit.
- Check whether a court appearance is required.
- Avoid missing the deadline while deciding how to respond.
- Consider how a conviction could affect your driving record, insurance, employment, or commercial license.
- Speak with a Missouri traffic attorney if you are unsure about your options.
You can also read what may happen when you simply pay a Missouri traffic ticket and how Missouri driver’s-license points work.
Frequently asked questions about Missouri SB 1408
Can I drive 75 mph everywhere in Missouri after August 28?
No. The new maximum applies only to rural interstates and qualifying freeways. Other roads remain subject to different limits, and a lower limit may be posted.
What if the interstate sign still says 70 mph?
Follow the posted 70-mph limit. The law treats the posted limit as presumptively legal for enforcement purposes.
Will every rural section of I-70 or I-44 immediately become 75 mph?
Not necessarily. Whether and when a particular segment is posted at 75 depends on the road classification and the limit established for that location. Drivers should rely on the posted sign rather than the highway number.
Does the new law change urban interstate speed limits?
The legislation specifically changes the uniform maximum for rural interstates and freeways. It does not automatically raise the statutory uniform limit for interstate highways, freeways, or expressways within urbanized areas to 75 mph.
Is there a grace period after a speed-limit sign changes?
Drivers should not expect a grace period. Once a speed limit is legally posted, it can be enforced.
Can I still challenge a speeding ticket?
A person charged with speeding may have options, but the available approach depends on the evidence, alleged speed, court, driving history, and other facts. No amendment, dismissal, or particular outcome can be promised.
Talk with McClain Law
If you received a Missouri speeding ticket or are concerned about points, a suspended license, or the effect of a traffic conviction, McClain Law can review the ticket and explain the available options.
McClain Law, LLC
Phone: (314) 970-5159
Email: t.mcclain@mcclain.law
Schedule a free 15-minute consultation
Official sources: Read the Missouri Senate bill summary and the final enacted text of SB 1408.
Related Missouri driving resources
- Missouri HB 1740: 2026 DWI law changes
- What to do in the first 15 days after a Missouri DWI arrest
- How Missouri driver’s-license points work
- Should you simply pay a Missouri traffic ticket?
Disclaimer: This post is for informational purposes only, does not constitute legal advice, and does not create an attorney-client relationship. Laws and their application can change, and every matter depends on its individual facts.