Why Self-Reported Fleet Data Can't Be Trusted (And What to Use Instead)

Every carrier profile on FMCSA's SAFER system includes a handful of numbers that look authoritative: power units, driver count, annual mileage, operation type, and cargo carried. These figures show up in risk models, underwriting decisions, and broker onboarding workflows as if they were verified facts. They aren't. Every one of them comes from a single source — the carrier's own MCS-150 filing — and there's almost no mechanism to verify any of it.

What the MCS-150 Actually Is

The MCS-150 is a registration and update form that every motor carrier with a USDOT number is required to file with FMCSA. It collects basic operational details:

• Power units — how many trucks the carrier operates
• Driver count — total drivers employed or contracted
• Annual mileage — estimated vehicle miles traveled per year
• Operation classification — authorized for-hire, exempt for-hire, private, etc.
• Cargo types — general freight, household goods, hazmat, and so on

The form is filed when a carrier first registers for a DOT number, and then updated biennially — every two years, based on the last two digits of the DOT number. There's no audit, no documentation requirement, and no cross-check against any other data source. The carrier fills in the numbers and submits.

Why the Data Is Unreliable

It's only updated every two years

A carrier that filed their MCS-150 in March 2024 isn't required to update it until March 2026. In two years, a fleet can double in size, shrink to a single truck, change cargo types entirely, or stop operating altogether. The data you're looking at may reflect a business that no longer exists in that form.

There's no verification

FMCSA does not verify any of the operational data on the MCS-150. There's no requirement to submit vehicle registration records, employment records, or mileage logs. A carrier with 3 trucks can report 50 power units. A carrier with 200 can report 15. Nothing in the filing process catches this.

Many carriers don't update at all

Despite the biennial requirement, a significant number of carriers fail to file their MCS-150 updates on time — or ever. FMCSA tracks whether a carrier's MCS-150 is current or outdated, but an outdated flag doesn't trigger automatic penalties. Carriers can continue operating with stale data on file for years.

Even "current" doesn't mean accurate

A carrier whose MCS-150 shows as current simply means the form was filed within the required window. It says nothing about whether the numbers on it reflect reality. A carrier could file their update on time, copy the same figures from two years ago, and be considered compliant.

Real-World Implications

The gap between reported fleet data and reality creates concrete problems for anyone relying on it.

Underwriting. A carrier reporting 50 power units might be priced as a mid-size fleet when they actually run 5 trucks. Or a growing carrier reporting the same 12 units from three years ago might actually be running 80, with the risk profile that entails.

Broker vetting. Load boards and broker systems often use power unit counts as a basic filter. A carrier inflating their fleet size can appear more established than they are, while a legitimate carrier that hasn't updated may look smaller.

Risk modeling. Any model that uses MCS-150 fleet data as an input is building on self-reported, infrequently updated, unverified numbers. Crash rates per power unit, violations per driver, mileage-adjusted incident rates — all of these calculations inherit the inaccuracy of the denominator.

Zero Power Units: A Specific Red Flag

Carriers reporting zero power units on their MCS-150 deserve particular attention. While there are edge cases (new registrants who haven't begun operations, carriers in the process of updating), a zero-unit filing combined with active authority is a known pattern for shell companies — entities that exist on paper to hold authority but don't operate trucks.

Shell carriers can be used to broker freight under the appearance of asset-based operations, to layer authority for chameleon carrier schemes, or simply to hold a DOT number for future sale (a practice FMCSA has moved to prohibit). A zero power unit count should always trigger further investigation rather than being dismissed as a data gap.

What to Use Instead

If self-reported fleet data is unreliable, what signals actually reflect a carrier's operational reality?

Inspection volume

The number of roadside inspections a carrier receives over a given period is one of the best proxies for actual fleet activity. Inspections happen to trucks on the road — you can't fake them, and you can't inflate them. A carrier claiming 50 trucks but showing 2 inspections in the past year is telling two different stories.

Insurance coverage levels

While insurance data has its own complexities, the coverage amounts a carrier maintains — particularly for liability and cargo — tend to correlate with actual fleet size and revenue. A carrier with $1M in liability coverage isn't running a 100-truck operation. Mismatches between reported fleet size and insurance levels are worth flagging.

Crash frequency relative to claimed fleet size

FMCSA crash records are filed by law enforcement, not the carrier. Comparing crash counts against the claimed fleet size and mileage can surface inconsistencies. A carrier reporting 5 power units and 100,000 annual miles with 8 reportable crashes in 24 months has a problem that the MCS-150 data alone wouldn't reveal.

Authority age combined with fleet size

New authority paired with a suspiciously large reported fleet size is worth questioning. A carrier that received their operating authority 3 months ago but reports 75 power units may be legitimate — they could be a well-funded startup — but the combination is unusual enough to warrant verification. On the other end, a 20-year-old authority still reporting 1 power unit may be dormant or operating in ways the record doesn't reflect.

Out-of-service rates

A carrier's vehicle and driver out-of-service rates from actual inspections tell you about the condition of the equipment that's actually on the road. This is observed data, not self-reported, and it's far more useful for risk assessment than a power unit count the carrier typed into a form.

The Bottom Line

The MCS-150 serves an administrative purpose — it gives FMCSA a baseline registration record for every carrier. But treating its operational data as ground truth for business decisions is a mistake. The numbers are self-reported, updated infrequently, never verified, and often stale.

The most reliable picture of a carrier's actual operations comes from observed data — inspections, crashes, insurance filings, and authority history — not from what the carrier chose to write on a form. Any serious carrier vetting process should weight these signals heavily and treat MCS-150 fleet data as one input among many, not as a source of record.