CSA Scores Explained: BASICs, Percentiles and How to Fix Errors
How FMCSA's Safety Measurement System turns roadside violations and crashes into percentiles, when a carrier gets flagged, how long violations count, and what the planned new methodology changes.
CSA scores are percentiles from FMCSA’s Safety Measurement System (SMS) that rank a motor carrier against similar carriers in seven safety categories, called BASICs, using 24 months of roadside inspections, crashes and investigation results. A higher percentile is worse. A carrier above the intervention threshold in a category, 65 percent for most general freight categories, can be prioritized for warning letters, targeted inspections or an investigation.
CSA stands for Compliance, Safety, Accountability, the enforcement program FMCSA launched in December 2010. SMS is the scoring system inside it. This guide reflects how SMS works as of November 2026.
What are the seven BASICs?
| BASIC | What feeds it | Threshold, general carriers | Threshold, hazmat carriers | Threshold, passenger carriers |
|---|---|---|---|---|
| Unsafe Driving | Speeding, reckless driving, phone use, seat belt and similar violations | 65% | 60% | 50% |
| Crash Indicator | State-reported crashes | 65% | 60% | 50% |
| Hours of Service Compliance | Logs, hours limits, ELD violations | 65% | 60% | 50% |
| Vehicle Maintenance | Brakes, lights, tires and other mechanical defects, cargo securement | 80% | 75% | 65% |
| Controlled Substances/Alcohol | Drug and alcohol violations found at roadside | 80% | 75% | 65% |
| Hazardous Materials Compliance | Placards, shipping papers, leaking containers | 80% | 80% | 80% |
| Driver Fitness | Invalid or wrong CDL, medical certificate, English proficiency | 80% | 75% | 65% |
Hazmat carriers and passenger carriers face lower thresholds because FMCSA treats their crashes as higher risk. The Crash Indicator and the percentiles for property carriers are not shown to the public.
How are CSA percentiles calculated?
Each violation from a roadside inspection is assigned to one BASIC and given a severity weight, with out-of-service violations weighted higher. The weight is then multiplied by a time weight: violations from the past 6 months count three times, 6 to 12 months count twice, and 12 to 24 months count once.
- FMCSA adds up the weighted violations in a BASIC.
- It divides that total by a measure of exposure: the number of relevant inspections for most BASICs, or the carrier’s power units and miles for Unsafe Driving and Crash Indicator.
- It compares the result with carriers in the same safety event group, meaning carriers with a similar number of inspections or crashes, and turns it into a percentile from 0 to 100.
A carrier needs a minimum amount of data in a BASIC before it gets a percentile, so a new or small carrier may show violations but no score. Clean inspections matter: they add to the inspection count without adding violations, which lowers the measure. The limits behind HOS Compliance violations are explained in our guide to hours of service rules.
Who can see a carrier’s CSA scores?
Since the FAST Act of 2015, percentiles and alerts for property carriers are hidden from the public SMS website. Passenger carrier percentiles remain public.
- The public, including shippers and brokers, can still see a property carrier’s inspections, violations, out-of-service rates, crash counts and registration data.
- A logged-in carrier sees its own percentiles and alerts.
- Enforcement users see percentiles for all carriers.
SMS results update monthly at FMCSA’s SMS website. The other public tools shippers use are covered in our guide on how to check a trucking company’s safety record.
How long do violations stay on your CSA record?
Violations and crashes count in SMS for 24 months from the date of the inspection or crash, losing weight as they age. After 24 months they drop out of the calculation.
They do not disappear everywhere. FMCSA’s Pre-Employment Screening Program, which carriers use when hiring drivers, shows a driver’s crashes from the past 5 years and inspections from the past 3 years. Violations that are tied to a driver follow that driver, while the carrier’s SMS reflects violations from inspections of its own trucks.
How do you challenge a violation through DataQs?
A carrier or driver who believes an inspection, violation or crash was recorded wrongly can file a request for data review (RDR) in FMCSA’s DataQs system. The request goes to the state agency that reported the data.
- Create a DataQs account and file the request against the specific inspection or crash report number.
- Explain what is wrong and attach evidence: repair receipts dated before the inspection, ELD records, photos, court dismissal papers or the police report.
- Under requirements FMCSA announced in April 2026, states open a request within 7 days and decide an initial review within 21 days.
- If denied, you may ask for reconsideration and then a final review, each by different reviewers, within 30 days of the previous decision.
The burden of proof is on the person filing. A citation that was dismissed or reduced in court is a recognized ground for a request, as long as you attach the court record. For crashes, FMCSA’s Crash Preventability Determination Program lets carriers ask that eligible crash types, such as being struck while legally parked, be marked not preventable and removed from the Crash Indicator calculation.
What changes are planned to the SMS methodology?
FMCSA announced an enhanced SMS in a Federal Register notice on November 20, 2024, after a preview and comment period that began in 2023. The main changes are:
- BASICs renamed compliance categories, with drug and alcohol violations and all operating-while-out-of-service violations moved into Unsafe Driving;
- a new Vehicle Maintenance: Driver Observed category for defects a driver should catch on a pre-trip inspection, such as lights;
- severity weights simplified from a 1 to 10 scale to 1 or 2;
- proportionate percentiles instead of safety event groups;
- percentiles calculated only for carriers with violations in the past 12 months in most categories.
FMCSA said a separate Federal Register notice would announce the launch date of the enhanced system, and as of November 2026 no such notice has been published. Until that launch, the BASIC methodology above remains in use, and carriers can compare their results under both through the Prioritization Preview on the CSA website.
Bottom line
CSA percentiles are relative, so a carrier’s score can rise even with no new violations if similar carriers improve. The quickest lever a carrier controls is the number of clean inspections, which come from well-maintained trucks and drivers whose lights, tires and logs pass a Level III or Level II without findings. Under the planned methodology, a carrier with no violations in the past 12 months would get no percentile in most categories at all.
FAQ
Do CSA scores affect a driver directly?
SMS scores carriers, not drivers. Drivers’ inspection and crash history appears in the Pre-Employment Screening Program, which employers check with the driver’s consent.
Is a high CSA score the same as a safety rating?
No. A safety rating of Satisfactory, Conditional or Unsatisfactory comes only from an FMCSA compliance review. CSA percentiles can lead to an investigation, which can then produce a rating.
Can a warning from an inspector hurt my CSA score?
Yes. Violations on the inspection report count in SMS even when no ticket is written. Only a ticket goes to court; the violation record goes to FMCSA either way.
How often are CSA scores updated?
Monthly. New inspections and crashes reported by states appear after processing, so a recent inspection may take a few weeks to show.
