ELD (Electronic Logging Device)
A device installed in commercial motor vehicles that automatically records driving time and hours of service. ELDs replaced paper logbooks and are mandated by FMCSA for most interstate carriers since December 2019. HOS violations captured by ELDs feed directly into a carrier's BASIC percentile scores tracked by CarrierOk.
Definition
An Electronic Logging Device (ELD) is a piece of hardware connected to a commercial motor vehicle's engine that automatically records driving time by monitoring the engine's status. ELDs became mandatory for most interstate carriers under the ELD Mandate (49 CFR Part 395), with full enforcement beginning December 16, 2019. The mandate replaced the previous paper logbook system, which was widely acknowledged to be easy to falsify. ELDs record four duty statuses: Off Duty, Sleeper Berth, Driving, and On Duty (Not Driving). Data is displayed on a screen in the cab and can be presented to law enforcement during roadside inspections via wireless transfer or screen display. ELDs must be registered with FMCSA and appear on the agency's registered device list. Exemptions exist for drivers operating vehicles manufactured before model year 2000, short-haul drivers who operate within a 150 air-mile radius, and drivers-salespersons. ELD data directly impacts a carrier's Hours-of-Service BASIC percentile — violations detected during inspections are recorded and flow into the SMS calculation. CarrierOk surfaces the HOS BASIC percentile (basic_percentile_hours_of_service) and alert flags that reflect ELD-era compliance patterns.
Why It Matters
For Underwriters
Post-ELD mandate, HOS violations carry more weight because they're harder to fabricate — a carrier with elevated HOS BASICs in the ELD era has genuine fatigue management problems, not just sloppy paperwork.
For Brokers
ELD compliance is table stakes — any carrier still operating without one (outside of exemptions) is not legally compliant and should be excluded from your approved carrier list.
For Developers
ELD status itself isn't a direct API field, but basic_percentile_hours_of_service and basic_alert_hours_of_service are the downstream signals that reflect ELD-captured compliance — use these to assess HOS risk.
In the API
/v2/profileRelated Fields
basic_percentile_hours_of_servicebasic_alert_hours_of_servicebasic_measure_hours_of_serviceinspections_totalviolations_totalFrequently Asked Questions
What is an ELD in trucking?
An ELD (Electronic Logging Device) is hardware connected to a truck's engine that automatically records driving time and duty status. It replaced paper logbooks to provide more accurate hours-of-service tracking. ELDs have been mandatory for most interstate commercial motor vehicles since December 2019. The device records Off Duty, Sleeper Berth, Driving, and On Duty (Not Driving) statuses.
Who is exempt from the ELD mandate?
Exemptions apply to drivers of vehicles manufactured before model year 2000, short-haul drivers operating within a 150 air-mile radius who return to their starting location daily, and drivers-salespersons. Additionally, drivers who use paper logs for 8 or fewer days in a 30-day period are exempt. These exemptions are narrowly defined and most interstate commercial drivers must use ELDs.
How do ELDs affect trucking insurance?
ELDs provide more accurate HOS compliance data, which flows into FMCSA's Safety Measurement System and BASIC percentile calculations. Carriers with clean ELD records tend to have lower HOS BASIC percentiles, which translates to better insurance eligibility and pricing. The ELD mandate has also reduced certain types of fatigue-related crashes, which benefits loss ratios across the industry.
Related Terms
HOS (Hours of Service)
Federal regulations limiting commercial driver operating hours to prevent fatigue-related crashes. Key limits include 11 hours driving, 14 hours on-duty, and mandatory 30-minute breaks. HOS violations are one of the 7 BASIC categories tracked in CarrierOk's BASIC percentile data.
BASIC Percentile
A 0-100 peer-relative safety score across seven FMCSA categories: Unsafe Driving, HOS, Vehicle Maintenance, Controlled Substances, Driver Fitness, Hazmat, and Crash Indicator. Higher is worse. CarrierOk computes all 7 BASICs including the two FMCSA withholds from public view.
CSA (Compliance, Safety, Accountability)
FMCSA's enforcement and compliance program that uses the Safety Measurement System to identify and prioritize high-risk motor carriers for intervention. CSA drives BASIC percentile scores, warning letters, and compliance reviews. CarrierOk provides all 7 BASIC percentiles, alert flags, and historical trend data via API.