CSA Score
A FMCSA safety measurement system score that rates commercial motor carriers and drivers across seven Behavior Analysis and Safety Improvement Categories (BASICs), used to prioritize roadside inspections and enforcement actions.
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This page is built to do more than define a term in one line. It explains what CSA Score means, why buyers keep seeing it while researching software, where it affects category and vendor evaluation, and which related topics are worth opening next.
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Compare ELD Compliance software →The Seven BASICs and What Each One Measures
How Percentile Thresholds Trigger Intervention
FMCSA does not publish a single pass/fail CSA score. Instead, carriers are ranked by percentile against peer carriers in the same category. Intervention thresholds vary by BASIC: Unsafe Driving and Crash Indicator thresholds sit at 65th percentile for passenger carriers and 75th percentile for general freight carriers. HOS Compliance, Driver Fitness, and Controlled Substances/Alcohol thresholds are set at 65th percentile for passenger carriers and 80th percentile for freight carriers. Vehicle Maintenance is set at 80th percentile for freight. Exceeding a threshold places a warning flag on the FMCSA's Safety Measurement System (SMS) public website, visible to shippers, brokers, and insurers — not just enforcement officers.
Real Operational Scenario: How a Score Compounds
The compounding problem most fleets miss
A mid-size refrigerated carrier in the Southeast ran 22 trucks on a regional distribution circuit. Over 18 months, drivers accumulated 14 HOS violations — mostly form-and-manner errors on paper logs before their ELD transition — and 9 vehicle maintenance violations for lighting defects found at pre-trip. None of these were catastrophic individually. But because CSA violations carry time-weighted severity points (more recent violations score higher) and are calculated across a rolling 24-month window, the carrier's HOS BASIC percentile climbed to 82, triggering an SMS warning flag. Within 60 days, two brokers pulled the carrier from their approved list pending a safety plan submission. The ELD switch reduced new HOS violations to near zero, but the legacy violations stayed in the window for another 18 months. The lesson: CSA improvement is a slow process because old violations don't fall off immediately.
Severity Weights by Violation Type
Each violation carries a base severity weight from 1 to 10. ELD malfunctions that result in HOS violations score a 5. Driving beyond the 11-hour driving limit scores a 7. Operating without a valid CDL scores a 10. A time weight multiplier is then applied: violations in the most recent 6 months are multiplied by 3, months 7–12 by 2, and months 13–24 by 1. A single high-severity violation from month 3 can outweigh three older violations from month 20. Fleets should prioritize eliminating current-cycle violations over worrying about violations already past the 18-month mark.
Practical Checklist: Reducing Your CSA Exposure
- Run a DataQ challenge within 60 days of any inspection showing a violation you believe was incorrectly recorded — FMCSA allows carriers to dispute inaccurate inspection data
- Conduct monthly internal SMS monitoring at fmcsa.dot.gov/safety/data-and-statistics/sms to catch percentile changes before they cross intervention thresholds
- Require drivers to complete DVIRs (Driver Vehicle Inspection Reports) before and after every shift — documented pre-trips are the primary defense against vehicle maintenance violations
- Transition remaining paper-log drivers to ELD — form-and-manner errors are the leading HOS BASIC driver for carriers still running hybrid operations
- Pull CSA data on every driver you're considering hiring using the Pre-Employment Screening Program (PSP) — driver violations follow them across carriers
- Schedule DOT-compliant annual vehicle inspections (49 CFR 396.17) and retain records for at least 14 months
- Review your Crash Indicator BASIC monthly — crashes that are not preventable can be challenged through the Crash Preventability Determination Program (CPDP)
CSA and Insurance: What Underwriters Actually Look At
Commercial trucking insurers routinely pull SMS data during underwriting renewals. Carriers with warning flags in Unsafe Driving or Crash Indicator BASICs often face surcharges of 15–40% over baseline premium. Some specialty markets refuse to quote carriers above the 75th percentile in two or more BASICs simultaneously. Fleets shopping for coverage should pull their own SMS printout before engaging insurers — knowing your percentile in advance lets you frame the narrative around corrective actions already taken rather than defending numbers cold.