Missouri raises interstate speed limits to 75 mph near Iowa, Arkansas
Four interstates near state borders will see new 75 mph limits by year-end, affecting carrier route planning and CSA speed-violation thresholds.
Missouri will raise speed limits to 75 mph on four interstates near the Iowa and Arkansas borders by the end of the year.
Which Missouri interstates are getting 75 mph speed limits?
The state plans to post new 75 mph limits on four interstates near its northern and southern borders. The change affects routes commonly used by carriers running Kansas City to Des Moines corridors and Memphis to Springfield lanes. Missouri has not yet published the specific milepost ranges or the effective date beyond "by the end of the year."
Carriers running these corridors should watch for updated signage and adjust route instructions to drivers. The change matters for CSA scoring: a speeding violation is measured against the posted limit, and a ticket at 76 mph in a former 70 mph zone carries different CSA percentile weight than the same speed in a current 70 mph zone.
How speed-limit changes affect CSA scores
FMCSA's Crash Indicator and Unsafe Driving BASICs count speeding violations based on how many mph over the limit a driver was cited. A citation for 15 mph or more over the limit carries heavier CSA severity weight than a citation for 6 to 10 mph over. When a state raises the limit from 70 to 75, a driver running 80 mph drops from a potential 10-over citation to a 5-over citation, which can mean the difference between a roadside inspection triggering an intervention threshold and staying below it.
Carriers with fleets governed at 68 to 72 mph will see no change in operations. Carriers running ungoverned or governed above 75 will need to remind drivers that 75 is the new ceiling, not a new floor. A citation at 85 mph in a 75 zone still lands in the 10-to-14-over severity bucket.
What carriers running Missouri routes need to do
Update driver route packets and dispatch instructions with the new limits once Missouri posts the effective date and milepost ranges. If your fleet uses telematics or ELD platforms that flag speeding events, confirm whether the platform pulls speed-limit data from a live map feed or requires manual updates. Some ELD vendors update speed-limit databases quarterly; others rely on HERE or TomTom feeds that refresh within days of a state posting new signage.
Carriers subject to ATA driving championships and CVSA inspector contest safety standards should brief drivers that higher posted limits do not override company speed policies. If your safety manual caps highway speed at 65 mph, the new 75 mph limit in Missouri does not change that internal rule.
Missouri joins a growing list of states with 75 mph or higher rural interstate limits. Texas, Kansas, Oklahoma, Nebraska, and South Dakota already post 75 or 80 mph on portions of their interstate systems. Carriers running multi-state lanes need to track which segments allow what speed, because a driver accustomed to 75 in Missouri who crosses into Illinois (where rural interstate limits remain 70) can pick up a citation within miles of the state line.
When the new limits take effect
Missouri has committed to posting the new limits by December 31, 2026, but has not published a specific date or the regulatory filing that would trigger the change. Carriers should monitor Missouri Department of Transportation announcements and watch for updated speed-limit signs on I-29 near the Iowa border and I-49 and I-55 segments near Arkansas. The state has not indicated whether all four interstates will switch on the same date or roll out in phases.
Once the limits are posted, they are enforceable immediately. There is no grace period. A citation issued the day new signage goes up counts for CSA and for state points on a CDL.
