By Michael Nielsen, Publisher | 15+ Years in Diesel Repair
Last Updated: October 2026
A CSA score is a percentile ranking that FMCSA's Safety Measurement System (SMS) assigns a motor carrier in each of seven safety categories, called BASICs, with a higher percentile meaning worse performance than similar carriers. There is no single number, and the percentiles are not safety ratings: FMCSA uses them to decide which carriers to prioritize for warning letters and investigations.
This Heavy Duty Journal guide checks the system against FMCSA's own documents, corrects several common claims about who can see your score, and covers the revised methodology FMCSA has announced. It does not quote insurance surcharges, freight premiums, or shipper cutoffs that could not be traced to a primary source.
Key Takeaways
- ✓There is no single CSA score. The SMS assigns a separate percentile in each BASIC, and a higher percentile means worse performance than peers.
- ✓Property carriers' percentiles are not public. Under section 5223 of the FAST Act, FMCSA removed percentiles and alerts from the public SMS site for property carriers, though inspection, crash, investigation, and registration data stay public.
- ✓Thresholds differ by BASIC and carrier type. For general property carriers the intervention threshold is 65 percent for Unsafe Driving, Crash Indicator, and HOS Compliance, and 80 percent for the other BASICs.
- ✓Not Preventable crashes are excluded. A crash FMCSA finds Not Preventable through the CPDP is excluded from the Crash Indicator measure and percentile, though it stays listed.
- ✓The methodology is changing. FMCSA's November 2024 notice describes a revised SMS, and sources disagree on whether it is live, so check the SMS site before acting on any chart.
In This Guide
CSA Score Explained: What It Is and What It Isn’t
Each month, the SMS measures two years of crash, inspection, and violation data. It sorts violations into BASICs, weights them by severity and recency, calculates a measure for each BASIC, and converts the measure into a percentile against comparable carriers. See FMCSA's SMS methodology document.
24 months
The window of crash, inspection, and violation data the SMS measures each month, per FMCSA's CSA site.
A percentile of 80 in a BASIC means the carrier performs worse than about 80 percent of its peers in that category. Lower is better, and each BASIC is independent, so a carrier can be above its threshold in one and fine in the rest. The SMS is not a safety rating: Satisfactory, Conditional, and Unsatisfactory ratings come from a compliance investigation under 49 CFR Part 385.
The Seven BASICs
- Unsafe Driving: speeding, reckless driving, improper lane changes, seatbelt, and phone violations.
- HOS Compliance: hours of service and logging violations under 49 CFR Part 395.
- Driver Fitness: invalid or expired CDLs, medical certification, and qualification problems. HDJ's CDL expiration tracking guide covers calendaring them.
- Controlled Substances/Alcohol: drug and alcohol violations.
- Vehicle Maintenance: equipment defects such as brakes, lighting, tires, and load securement.
- HM Compliance: hazardous materials handling, marking, and paperwork violations, and not publicly available.
- Crash Indicator: a carrier's pattern of crash involvement, also not publicly available.
Every recordable crash entered the Crash Indicator historically, regardless of fault. FMCSA's Crash Preventability Determination Program (CPDP) now lets carriers submit eligible crashes for review, covered below.
How the SMS Calculates Percentiles
The calculation has four parts you can influence. Each violation carries a severity weight, so a brake out-of-service violation counts more than a minor equipment item. More recent violations count more than older ones within the 24-month window. The measure is normalized for how much a carrier operates, and the result is compared with other carriers to produce a percentile.
Because the percentile is relative, it can move even in a month with no new inspections if other carriers' data changes. FMCSA's notices describe peer groupings called safety event groups in the legacy method, so a fleet is compared with carriers that have a similar number of safety events, not simply fleet size.
For improvement, the practical point is simple: stop new violations, correct wrong ones, and let old ones age out. A cluster of recent violations hurts more than the same cluster a year ago, which is why prompt action beats waiting.
Intervention Thresholds and What Follows
FMCSA prioritizes carriers for interventions when a BASIC percentile reaches its threshold, and the threshold depends on the BASIC and the carrier type. The values below come from FMCSA's February 2023 Federal Register notice and its methodology document.
| BASIC | General property | HM carrier | Passenger carrier |
|---|---|---|---|
| Unsafe Driving, Crash Indicator, HOS Compliance | 65th | 60th | 50th |
| Vehicle Maintenance, Controlled Substances/Alcohol, Driver Fitness | 80th | 75th | 65th |
| HM Compliance | 80th | 80th | 80th |
A carrier at or above a threshold may get a warning letter, an offsite or onsite investigation, or a cooperative safety plan, with the response escalating if performance does not improve. The SMS also considers acute and critical violations found in investigations, so a percentile below the threshold is not a guarantee of no contact.
Key Recommendation
Log in to the SMS every month, read each new inspection line by line, and decide the same week whether any record needs a DataQs challenge.
Who Can See Your CSA Score
Many guides say CSA data is public and that shippers and insurers see your BASIC percentiles. For property carriers that is not correct. Under section 5223 of the FAST Act, FMCSA removed SMS percentiles and alerts from the public SMS website for property carriers. Passenger carrier percentiles stay public, and inspection, investigation, crash, and registration data are public for all carriers. See the 2024 Federal Register notice.
A property carrier sees its own percentiles by logging in to the SMS. Brokers, shippers, and insurers can still read the public inspection, violation, and crash data, and some use third-party tools that estimate a score, so what an outsider sees may not match your login. The public SMS site is where anyone can look up your public records.
Do not rely on commonly quoted insurance surcharges or shipper cutoffs. Those figures came from unsourced claims, and the effect on premiums and freight depends on the insurer, the broker, and the data each one uses. Ask your insurer and your top customers what they look at.
Reviewing and Correcting Your Data
Roadside data contains errors: a violation attached to the wrong USDOT number, a wrong citation, or a crash that was not the carrier's fault. FMCSA's DataQs system lets carriers request a review of a record, and you should challenge a record with documentation such as photos, repair orders, and driver statements. Time limits and procedures can change, so confirm them in DataQs before relying on a deadline.
For crashes, the CPDP lets carriers and drivers submit evidence through DataQs that an eligible crash was not preventable. FMCSA's CPDP FAQ says Not Preventable crashes are excluded from the Crash Indicator BASIC, remain listed in a separate table, and are noted in the Pre-Employment Screening Program record.
Keep the driver side in mind. A new hire's history shows up in the Pre-Employment Screening Program, which carriers can check with the driver's consent, and violations are attributed to the carrier a driver operates for at the time of inspection. HDJ's FMCSA compliance requirements guide covers the wider compliance picture.
Free DOT Status Check
Enter a USDOT number and quickly review public carrier status, operating authority and key FMCSA registration data.
Improving Your CSA Score
Match the effort to the BASIC. For Vehicle Maintenance, a real pre-trip inspection and a closed loop from defect report to repair is the control, and HDJ's annual vehicle inspection requirements guide covers the inspection side. For HOS, review ELD data back-office on a schedule. For Driver Fitness, calendar credential dates. For Unsafe Driving, coach by driver using each driver's own inspection history.
HDJ's fleet driver safety program guide covers training, monitoring, and incident response as a system, and its CSA score improvement strategies and CSA score management guides go deeper on the improvement steps. Use the thresholds above to decide which BASIC to fix first.
A short priority rule works: fix BASICs closest to their threshold first, challenge records that are wrong, and document corrective actions in case an investigator asks. Do not assume that driver coaching and equipment fixes will show up immediately, because the SMS updates monthly and recent data carries more weight.
Changes to the SMS Methodology
FMCSA published its Enhanced Carrier Safety Measurement System notice in November 2024. It describes a revised SMS with renamed categories, consolidated violations, percentile scoring that replaces safety event groups, and revised intervention thresholds. FMCSA also offered a Prioritization Preview so carriers could see projected results.
Sources disagree on timing. Some trade sources say the revised system is rolling out in 2026, while others say the existing system remains in effect until FMCSA announces a launch date, and FMCSA's methodology document I could read still described the current BASICs and thresholds. Check the SMS site and FMCSA's CSA pages for the current method before you rely on the numbers in this article or on any chart.
Frequently Asked Questions
What is a good CSA score?
There is no official "good" score. Lower percentiles are better, and the practical target is staying below your BASIC thresholds, which are 65 or 80 percent for general property carriers depending on the BASIC.
Can shippers see my CSA percentiles?
Not for property carriers. FMCSA removed percentiles and alerts from the public SMS site under the FAST Act, though inspection, crash, and investigation data remain public for all carriers.
How long does a violation count?
The SMS measures 24 months of data, and recent violations weigh more than older ones. A successful DataQs challenge can correct an inaccurate record before it ages out.
Does a crash that was not my fault hurt my score?
It can. Crashes entered the Crash Indicator regardless of fault, but a crash FMCSA finds Not Preventable through the CPDP is excluded from the measure and percentile.
How often does the SMS update?
Monthly. Check your login after each update, read every new record, and decide that week whether to file a DataQs challenge. The data window is 24 months, so each update also ages out the oldest records.
The Bottom Line
A CSA score is a set of monthly percentiles that FMCSA uses to prioritize carriers, not one number and not a safety rating. The most useful corrections are that property carriers' percentiles are not public and that a Not Preventable crash is excluded from the Crash Indicator.
Heavy Duty Journal's guidance at heavydutyjournal.com, from publisher Michael Nielsen and the HDJ editorial team, is to work from your own SMS login, challenge wrong records, and verify any chart or number against FMCSA's current documents.
As of October 2026, the status of FMCSA's revised SMS methodology is unclear in the sources reviewed, so confirm it on the SMS site.
Share This With Your Safety Manager
Know someone still quoting a public CSA percentile for a property carrier? Pass this along so they work from the real data.
