What are CSA scores and how do they work?
CSA scores are percentiles that FMCSA's Safety Measurement System calculates from your roadside inspections, violations and crashes, grouped into categories called BASICs. Recent and more severe violations count more, and the score compares you to carriers of similar size. High percentiles can lead to warning letters, investigations and fewer brokers willing to load you.
CSA scores are how the Federal Motor Carrier Safety Administration (FMCSA) sorts carriers by safety performance between full audits. Brokers, shippers and insurers look at the same data, so your numbers can affect whether you get loaded and what you pay for coverage.
What CSA is
CSA stands for Compliance, Safety, Accountability. It is FMCSA's enforcement program, and its scoring engine is the Safety Measurement System (SMS). SMS takes data from:
- Roadside inspections and the violations written on them,
- Reportable crashes,
- Investigation results.
It then groups that data into categories and compares your carrier to others with a similar amount of activity. The result is a percentile from 0 to 100 in each category. Higher is worse: a percentile of 80 means your measure is worse than about 80% of similar carriers.
FMCSA has been working on changes to the SMS methodology, including how categories are grouped and how carriers are compared. The basics below describe how the system has generally worked; check FMCSA's CSA website for the current version.
The seven BASICs
SMS sorts data into Behavior Analysis and Safety Improvement Categories, or BASICs:
| BASIC | What feeds it |
|---|---|
| Unsafe Driving | Speeding, improper lane changes, texting, seat belt, reckless driving |
| Crash Indicator | Reportable crash history |
| Hours-of-Service Compliance | Logbook and ELD violations, driving over hours |
| Vehicle Maintenance | Brakes, lights, tires, other defects (cargo securement is also scored here in the current system) |
| Controlled Substances/Alcohol | Drug or alcohol possession or use violations |
| Hazardous Materials Compliance | Placarding, shipping papers, packaging |
| Driver Fitness | Invalid license, missing medical certificate, unqualified driver |
Each BASIC has an intervention threshold. Thresholds are lower (stricter) for passenger carriers and hazmat carriers, and some BASICs are treated as higher-risk than others. Cross a threshold and you may be flagged for an FMCSA intervention. Some percentiles, such as the Crash Indicator, are not shown to the public.
How the score is calculated
You do not need the full formula, but three ideas explain most of it.
1. Severity weight
Each violation carries a severity weight, roughly 1 to 10. A minor paperwork issue weighs much less than a brake or tire defect. Violations that put a driver or vehicle out of service get extra weight. See our guide to out-of-service criteria.
2. Time weight
SMS generally looks at the last 24 months. Recent events count more:
- Last 6 months: highest weight
- 6 to 12 months: medium weight
- 12 to 24 months: lowest weight
After 24 months the event drops out of the SMS calculation.
3. Normalizing by exposure
Your weighted violations are divided by your exposure, such as the number of relevant inspections or, for some BASICs, a measure based on power units and miles. This is why one bad inspection hurts a small carrier with few inspections far more than a large fleet.
Worked example: why clean inspections matter
Take a simplified example. These numbers are hypothetical and the real formula has more parts.
- A one-truck carrier has 2 inspections in the Vehicle Maintenance BASIC. One has a lighting violation with a weighted total of 6. Measure: 6 / 2 = 3.0.
- Over the next months the truck gets 4 more clean inspections. Same violation, now 6 / 6 = 1.0.
- As that violation ages past 6 and 12 months, its time weight drops, so the measure falls further.
The lesson: one violation on a thin record looks bad, and the cure is time plus clean inspections. That is also why a Level I inspection with no violations is a good outcome, not a hassle. Our guide to DOT roadside inspections explains how to prepare.
What happens when scores are high
FMCSA uses a stepped approach. Depending on your data, it may:
- Send a warning letter,
- Conduct an offsite or onsite investigation,
- Require a corrective action plan,
- In serious cases, issue a proposed safety rating or penalties.
Outside FMCSA, high percentiles can mean brokers decline to set you up, shippers reject you, and insurance quotes go up. A new authority also faces the new entrant safety audit, where poor roadside results can count against you.
How to keep your CSA scores low
Before the trip
- Do a real pre-trip inspection every day. Lights, tires and brakes cause many vehicle violations.
- Fix defects before dispatch, not "next week."
- Keep the cab paperwork current: registration, insurance, annual inspection, medical card, ELD instruction sheet and blank paper logs.
On the road
- Run legal hours and keep ELD logs accurate. Our guide to hours of service covers the 11, 14 and 70-hour rules.
- Avoid speeding and phone use. Unsafe Driving violations tend to be weighted heavily.
- Wear a seat belt. It is an easy violation to avoid.
After the inspection
- Read every report before the driver leaves the scale.
- If a violation is wrong, dispute it through FMCSA's DataQs system. See how to dispute a violation with DataQs.
- Check your SMS profile monthly so you see problems before a broker does.
Checking your own data
You can view your public SMS results on FMCSA's website by USDOT number. Logging in to the FMCSA portal shows more detail, including non-public BASICs. Review each inspection for accuracy: right USDOT number, right truck, right driver. Inspections are sometimes assigned to the wrong carrier, and you can request a correction through DataQs.
How Texas Solutions can help
Texas Solutions is a dispatch service, not a broker or motor carrier. Our dispatchers find and negotiate loads, handle broker packets and paperwork, and work 24/7, and you approve every load. We plan loads around legal hours so drivers are not pushed into violations. See our owner-operator dispatch service or talk to a dispatcher.
Frequently asked questions
Is a CSA score the same as a safety rating?
No. A safety rating (Satisfactory, Conditional or Unsatisfactory) comes from an FMCSA compliance review or investigation. CSA percentiles are calculated automatically from inspection and crash data and change over time.
How long do violations affect my CSA scores?
The Safety Measurement System generally uses the most recent 24 months of inspection data, with older events weighted less. Inspection and crash records can remain visible in other FMCSA systems, such as driver pre-employment screening, for longer.
Why does my new authority show no CSA percentile?
A carrier needs a minimum amount of inspection or crash data in a BASIC before a percentile is calculated. Many new carriers have too few inspections, so the BASIC shows insufficient data rather than a score.
Can clean inspections lower my CSA scores?
They can help. Measures are generally based on violations relative to the number of relevant inspections, so inspections with no violations add to the base and can improve your measure over time.
