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What Are FMCSA BASIC Percentiles? A Complete Guide

CarrierOk Team||6 min read

If you work in freight brokerage, insurance underwriting, or carrier compliance, you have almost certainly encountered BASIC percentiles. They are the backbone of FMCSA's Safety Measurement System (SMS) and the primary way the federal government evaluates a motor carrier's safety performance relative to its peers.

Despite their importance, BASIC percentiles are frequently misunderstood. This guide breaks down what they are, how they are calculated, why FMCSA hides two of the seven categories, and how you can access the full picture through CarrierOk's BASIC Percentiles API.

What Does BASIC Stand For?

BASIC stands for Behavior Analysis and Safety Improvement Categories. FMCSA uses seven BASICs to organize and evaluate the safety performance of every active motor carrier in the United States. Each BASIC represents a distinct dimension of operational risk.

The 7 FMCSA BASICs

Here are all seven categories with their full names and a brief explanation of what each measures:

  1. Unsafe Driving — Violations related to speeding, reckless driving, improper lane changes, texting while driving, and other dangerous on-road behaviors observed during roadside inspections.
  2. Hours-of-Service (HOS) Compliance — Violations related to driver working hours, including exceeding maximum driving time, falsifying logs, and operating without a required ELD (Electronic Logging Device).
  3. Vehicle Maintenance — Violations related to the mechanical condition of commercial motor vehicles, including brake defects, tire issues, lighting failures, and other equipment problems found during inspections.
  4. Controlled Substances / Alcohol — Violations related to the use or possession of controlled substances or alcohol by drivers, including positive drug tests and refusal to submit to testing.
  5. Driver Fitness — Violations related to driver qualification, such as operating without a valid CDL, failure to maintain medical certificates, and lack of required endorsements.
  6. Hazardous Materials (Hazmat) Compliance — Violations related to the safe handling, labeling, placarding, and transportation of hazardous materials. This BASIC applies only to carriers that transport hazmat.
  7. Crash Indicator — A measure based on the carrier's history of state-reported crashes, including the frequency and severity of those crashes relative to the carrier's exposure (vehicle miles traveled or power units).

How Are BASIC Percentiles Calculated?

FMCSA calculates BASIC percentiles using a 24-month rolling window of inspection and crash data. Here is the process at a high level:

  1. Violation data collection — FMCSA collects inspection reports from roadside inspections conducted across the country. Each inspection can generate zero or more violations, and each violation is assigned to the relevant BASIC category.
  2. Time weighting — More recent violations carry more weight than older ones. Violations from the most recent 6 months are weighted most heavily, with weight decreasing for older violations within the 24-month window.
  3. Severity weighting — Each violation type has a severity weight assigned by FMCSA. More serious violations (such as operating while fatigued or brake system failures) receive higher weights than minor infractions.
  4. Carrier measure calculation — The weighted violations are summed and normalized by the carrier's exposure (typically the number of inspections in that BASIC category) to produce a raw measure for each BASIC.
  5. Peer group comparison — Carriers are grouped into peer groups based on the number of relevant inspections they have received. The carrier's measure is then compared against all other carriers in the same peer group, producing a percentile rank from 0 to 100.

A percentile of 75 means the carrier's safety performance in that category is worse than 75% of its peers. Higher percentiles indicate worse performance, not better. This is the single most common misconception about BASIC percentiles.

Key takeaway: BASIC percentiles are inverse — a higher number means worse safety performance. A carrier at the 90th percentile is more dangerous than 90% of its peers, not safer.

Why FMCSA Only Publishes 5 of 7 BASICs

If you visit the FMCSA SMS website, you will only see percentile scores for five of the seven BASICs. The two hidden categories are Crash Indicator and Hazmat Compliance.

FMCSA withholds these two BASICs from public view due to ongoing concerns about data accuracy and accountability. In particular:

  • Crash Indicator — FMCSA's crash data does not account for fault. A carrier involved in crashes that were entirely caused by other drivers will still accumulate points in the Crash Indicator. The agency has faced criticism for publishing crash-based scores without a fault determination, and has kept the Crash Indicator hidden from public SMS results since 2013.
  • Hazmat Compliance — This BASIC applies to a smaller subset of carriers and has a thinner data pool, which can lead to less statistically reliable percentiles. FMCSA has opted not to publish it publicly, though it remains available for internal use during compliance reviews.

For risk assessment professionals, this creates a significant blind spot. Crash history and hazmat violations are two of the most material factors in evaluating carrier risk, yet the official public portal does not surface them.

Bottom line: FMCSA hides Crash Indicator and Hazmat Compliance percentiles from the public SMS portal. If you rely only on the public data, you are missing two of the most critical risk dimensions.

What Percentile Thresholds Trigger FMCSA Intervention?

FMCSA uses BASIC percentiles to prioritize carriers for investigation and intervention. The agency has established intervention thresholds that vary by category:

  • Unsafe Driving — 65th percentile
  • Hours-of-Service Compliance — 65th percentile
  • Vehicle Maintenance — 80th percentile
  • Controlled Substances / Alcohol — 80th percentile
  • Driver Fitness — 80th percentile
  • Hazmat Compliance — 80th percentile
  • Crash Indicator — 65th percentile

When a carrier exceeds the threshold in one or more BASICs, they become eligible for a warning letter, targeted investigation, or compliance review. Exceeding thresholds in multiple BASICs simultaneously significantly increases the likelihood of enforcement action.

What Does "Insufficient Data" Mean?

A carrier may show "Insufficient Data" for a BASIC if they have not received enough inspections in that category within the 24-month window to be placed in a peer group. This does not mean the carrier is safe — it simply means there is not enough inspection data to calculate a reliable percentile. New entrant carriers and small fleets often have insufficient data across multiple BASICs.

How CarrierOk Provides All 7 BASICs

CarrierOk computes percentile scores for all seven BASICs, including the two that FMCSA withholds from public view. We replicate the FMCSA methodology using source inspection and crash data, apply the same time and severity weighting, and calculate peer-group percentiles across our full dataset, which covers every FMCSA registrant.

The result is a complete safety profile for every carrier, accessible via the BASIC Percentiles API or the CarrierOk platform. Every API response includes all seven percentile scores, the underlying violation counts, and the inspection counts used in the calculation.

Why Complete BASIC Visibility Matters

Whether you are an insurance underwriter pricing a new policy, a freight broker onboarding a carrier, or a factoring company evaluating credit risk, having visibility into all seven BASICs gives you a materially better risk picture. The Crash Indicator in particular is one of the strongest predictors of future loss exposure, and operating without it is like underwriting with one eye closed.

CarrierOk was built to close this gap. Start a free trial and see the full BASIC profile for any carrier in seconds.

Last updated: April 20, 2026
FAQ
FMCSA intervention thresholds vary by category. Unsafe Driving, HOS Compliance, and Crash Indicator trigger at the 65th percentile. Vehicle Maintenance, Controlled Substances/Alcohol, Driver Fitness, and Hazmat Compliance trigger at the 80th percentile. Exceeding thresholds in multiple categories simultaneously increases the likelihood of enforcement action.
Insufficient data means the carrier has not had enough inspections in that BASIC category within the 24-month evaluation window to be placed in a peer group and receive a percentile score. It does not indicate safety — only that there is not enough data available for comparison. New entrant carriers and small fleets often show insufficient data.
FMCSA recalculates BASIC percentiles on a monthly cycle using the most recent 24 months of inspection and crash data. However, underlying inspection data can take up to 90 days to appear in the system after a roadside event. CarrierOk re-ingests the moment FMCSA publishes an update and recomputes percentiles then, so scores follow the source rather than a fixed schedule.
FMCSA does not offer a public API for BASIC percentile scores. CarrierOk provides all 7 BASIC percentiles through its REST API, including Crash Indicator and Hazmat Compliance, which FMCSA withholds from public view. You can retrieve full BASIC profiles by DOT number, MC number, or legal name.

See the full carrier risk picture.

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