FMCSA Filings and Proof of Insurance: BMC-91, BMC-91X, and BMC-34 Explained

Before you can haul freight under your own motor carrier authority, FMCSA requires proof that you carry the required insurance. This proof comes in the form of specific filings that your insurer submits electronically to the Unified Registration System (URS).

Form BMC-91: Primary Liability Certification

The BMC-91 (Endorsement for Motor Carrier Policies of Insurance for Public Liability) is filed by your insurer to certify that you carry the required primary liability coverage. It is not a separate policy — it is an endorsement attached to your primary auto liability policy.

When the BMC-91 is on file, FMCSA can confirm that your carrier authority is backed by the required insurance. Without it, your authority cannot become active.

Form BMC-91X: Excess Liability

The BMC-91X serves the same purpose as the BMC-91 but is used for excess or umbrella liability coverage. If your primary liability policy is at $1,000,000 and you carry additional excess coverage, the BMC-91X documents the excess layer.

Form BMC-34: Cargo and Liability Bond

The BMC-34 is filed by property brokers and freight forwarders, not by carriers, as a surety bond demonstrating financial responsibility. If you operate as a broker in addition to a carrier, you may need both carrier insurance filings and the BMC-34.

The MCS-90 Endorsement

The MCS-90 is separate from the BMC filings but equally important. It is an endorsement on your liability policy that obligates your insurer to pay a valid claim even if a policy exclusion, condition, or cancellation would otherwise deny the claim. It is the federal government's backstop ensuring that injured parties can recover from your insurer.

What Happens If Coverage Lapses

If your insurer cancels your policy or your premium payment lapses, they are required to file a cancellation notice with FMCSA. FMCSA will then revoke your operating authority. You cannot legally haul freight with revoked authority.

Reinstating revoked authority requires new insurance filings and potentially additional regulatory steps. The gap in authority also becomes part of your carrier history, which can affect future insurance pricing.

Keeping Track of Your Filings

Log into the FMCSA SAFER system regularly to verify that your insurance filings are current and active. Do not assume your insurer has filed correctly — verify it yourself. Errors happen, and the consequences of lapsed filings are severe.