Short answer
The MCS-90 is a federally prescribed endorsement attached to a motor carrier’s auto liability policy. It promises that injured members of the public will be paid up to the federal minimum, even if the policy itself would not cover the accident, and it lets the insurer recover that payment from the carrier afterward.
- It protects the public, not the trucking company. If the MCS-90 is the only reason a claim got paid, expect a reimbursement demand.
- It is not issued per truck. FMCSA says it attaches to the policy and applies to all vehicles operated under that policy that are subject to federal financial responsibility rules.
Where the MCS-90 comes from
The MCS-90 is required by 49 CFR 387.15 and mandated by sections 29 and 30 of the Motor Carrier Act of 1980. Under 49 CFR 387.7(d), the carrier's proof of financial responsibility is the MCS-90 issued by its insurer (or an MCS-82 surety bond, or FMCSA approval to self-insure), and that proof has to be kept at the carrier's principal place of business and produced on reasonable request from the public.
It is different from the BMC-91X. The BMC-91X is a filing the insurer sends to FMCSA. The MCS-90 is an endorsement that lives on your policy. For-hire interstate carriers typically have both. Private carriers hauling hazardous materials in the quantities listed in 49 CFR 387.9 need the MCS-90 even though they do not hold for-hire authority.
Which filing goes where
How it works in a claim
IRMI describes the MCS-90 as something that "does not actually provide insurance except on a reimbursement basis." Here is the sequence when it matters:
- A truck operated under your authority causes an accident that injures someone or damages their property.
- Your policy would not normally respond. Common reasons: the truck was not listed on a scheduled policy, the driver was excluded, or a policy condition was breached.
- Because of the MCS-90, the insurer still pays a final judgment to the injured party, up to the federal minimum that applies to your operation.
- The insurer then has the right to seek reimbursement from you.
That last step is why carriers should not treat the MCS-90 as a safety net. It keeps the public whole. It does not keep your company whole.
What the MCS-90 does not do
- It does not raise your limits. It is tied to the federal minimum for your commodity class, which is $750,000 for general freight in trucks of 10,001 pounds or more. See FMCSA truck insurance minimums.
- It does not cover your own truck, your cargo, or your own injuries. Physical damage and cargo are separate coverages.
- It does not satisfy a broker contract. Brokers ask for policy limits and wording, not for the federal guarantee. See why brokers require $1 million.
- It does not apply to Texas intrastate-only operations as a substitute for the Texas filing. Texas uses its own Form E process. See what is Texas Form E.
Cancellation of the endorsement
Under 49 CFR 387.7(b), the policy and endorsement stay in effect continuously until terminated, and either the insurer or the carrier can cancel by giving the other 35 days' written notice. The separate FMCSA filing has its own 30-day notice rule. The practical point: an MCS-90 obligation can outlast the date you thought you were done with an old policy, which is one more reason not to let coverage lapse between insurers.
The real-world lesson
Most MCS-90 surprises start with a truck that was never added to the policy or a driver who was never approved. Keep the unit list and driver list current, and you rarely have to learn how reimbursement works.
Common questions
Do I need a separate MCS-90 for each truck?
No. FMCSA says the endorsement is attached to the policy and applies to all vehicles operated under it that are subject to the federal financial responsibility rules.
Will a broker ask to see my MCS-90?
Some onboarding packets ask for it. More often they check your FMCSA filing and a certificate of insurance showing your actual limits.
If the insurer pays under the MCS-90, will I owe the money back?
That is how the endorsement is designed. When the policy would not have covered the loss on its own terms, the insurer pays the public and can seek reimbursement from the carrier.
Sources
- FMCSA, Form MCS-90 Endorsement. Regulatory basis (49 CFR 387.15, Motor Carrier Act of 1980) and that the endorsement attaches to the policy, not to individual vehicles.
- 49 CFR 387.7, Financial responsibility required (eCFR). Proof of financial responsibility kept at principal place of business; 35-day cancellation notice.
- IRMI, MCS-90 endorsement (glossary). Reimbursement basis of the endorsement.
- 49 CFR 387.9, Financial responsibility, minimum levels (eCFR). Minimum amounts and private hazmat carriers.
This page explains insurance, not law. Have your attorney review indemnity and contract language; our job is making the insurance match it.
Keep reading
Questions
What is a BMC-91X filing?
Coverage
Primary truck liability: what it covers, what the law requires, and where it breaks
Contracts and deadlines
Which insurance filings does a Texas trucking company need, and who files them?
Questions
What is the difference between scheduled auto and any auto?
Questions
What are the FMCSA minimum insurance limits for trucks?