A plain-English guide to CSA scores.
What FMCSA measures, how the thresholds work, why you can't see your percentiles on the public site, and what actually brings a score down.
What CSA is
CSA, short for Compliance, Safety, Accountability, is FMCSA's program for finding and acting on carriers with safety problems. Its scoring system is the Safety Measurement System, or SMS. SMS takes the results of your roadside inspections and crash reports from the last 24 months and turns them into a measure for each of seven safety categories, called BASICs.
FMCSA then compares your measure with other carriers that have a similar amount of inspection data and gives you a percentile from 0 to 100. A higher percentile means a worse record. SMS results are updated once a month.
The seven BASICs and their thresholds
Each BASIC has an intervention threshold. If your percentile is at or above it, FMCSA is more likely to act. The thresholds are lower for passenger carriers and hazardous materials carriers.
| BASIC | What it covers | General threshold | Hazmat | Passenger |
|---|---|---|---|---|
| Unsafe Driving | Speeding, reckless driving, improper lane changes, phone use, seat belts | 65% | 60% | 50% |
| Crash Indicator | History of reportable crashes | 65% | 60% | 50% |
| Hours-of-Service Compliance | Driving and on-duty limits, logs and ELD records | 65% | 60% | 50% |
| Vehicle Maintenance | Brakes, lights, tires and other defects, plus inspection and repair records | 80% | 75% | 65% |
| Controlled Substances and Alcohol | Drug or alcohol use and possession | 80% | 75% | 65% |
| Hazardous Materials Compliance | Placards, shipping papers, securement of hazardous materials | 80% | 80% | 80% |
| Driver Fitness | Licensing, medical certification and driver qualification | 80% | 75% | 65% |
How the measures are calculated
Every violation has a severity weight from 1 to 10. Newer violations count more than older ones: inspections from the last six months count three times as much as those from a year or two ago. Violations that led to an out-of-service order carry extra weight.
For most BASICs, the total is divided by how many relevant inspections you had. That's why clean inspections help: an inspection with no violations still counts in the denominator and pulls your measure down. Unsafe Driving and the Crash Indicator are measured against the size of your fleet instead.
You also need a minimum amount of data before a percentile is assigned. A small fleet with only a few inspections may have no percentile at all in some BASICs.
Why you can't see your percentiles on the public site
Since a 2015 federal law, FMCSA no longer shows percentiles or threshold markers for property carriers on the public SMS website. Your inspection and violation details are still public. Passenger carrier percentiles are still public too.
You can still see your own percentiles by logging in to FMCSA's site with your carrier account. FMCSA, state enforcement and many insurers still use them. Because the inputs are public, we can rebuild a close estimate of your standing from your inspection history and track it every month.
When we report your standing, we call it an estimate, because it is one. Your official percentiles are the ones you see when you log in to FMCSA's site, and we'll gladly compare the two with you.
What happens when you're over a threshold
Being over a threshold doesn't change your safety rating by itself. It makes you a higher priority for FMCSA. Depending on how many BASICs are over and by how much, the next step can be:
- A warning letter explaining the problem and what's expected.
- More roadside inspections, because your trucks are flagged when they're scanned at the roadside.
- An investigation, either offsite by records request or onsite at your place of business. Investigations can be focused on one area or cover your whole operation, and they can result in a proposed safety rating and fines.
What actually brings a score down
- Fix the cause. If the same violation keeps showing up, the score won't move until the habit or the paperwork behind it changes.
- Get clean inspections. Each inspection with no violations counts in your favor in most BASICs.
- Let time work. Violations lose weight as they age and drop off after 24 months. Knowing which ones are about to age out helps you plan.
- Challenge errors. If an inspection is wrong, request a correction through DataQs.
How DataQs works
DataQs is FMCSA's system for asking that data be reviewed. Requests about a roadside inspection go to the state agency that did the inspection, which decides whether to change it. Common reasons to file include duplicate inspections, inspections assigned to the wrong carrier, and violations that were dismissed or found not guilty in court.
A good request is specific, short, and backed by documents. A request without evidence usually goes nowhere, so we only file when the record supports it.
Changes coming to CSA
FMCSA has been working on changes to how SMS organizes and scores safety data. We follow those changes and will tell you what they mean for your fleet before they take effect.
This guide is general information about FMCSA programs, last reviewed in November 2026. It is not legal advice. For the official rules, see FMCSA's website and Title 49 of the Code of Federal Regulations.
Want to know where you stand?
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