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Certificates of insurance for mills and plants: a carrier's guide

Helm PartnersUpdated Oct 29, 2026Sources checked Oct 29, 2026

This guide is general information, not advice on any policy.

Short answer

A mill or plant usually asks for a certificate showing your auto liability, cargo and general liability limits, and often for additional insured status and a waiver of subrogation. A certificate shows coverage on the day it is issued. It does not add or change coverage, so any term the plant needs must be on the policy itself.

In this guide
  • What a certificate is
  • What mills and plants ask for
  • Terms that need the policy
  • Keeping requests in order
  • A checklist
  • FAQ

Flatbed carriers serving steel mills, service centers and plants deal with a steady flow of certificate requests. Each facility has its own list. Here is what those requests usually include, what a certificate can and cannot do, and how to keep them in order.

What a certificate is

  • A certificate of insurance summarizes your policies on the day it is issued: insurer, policy numbers, dates and limits.
  • It does not add, extend or change coverage. Terms a facility needs have to be on the policy.

What mills and plants ask for

  • Auto liability limits, often above the $750,000 federal floor for for-hire freight vehicles rated 10,001 pounds or more (49 CFR 387.303T).
  • Motor truck cargo limits, sometimes sized to the value of a coil or bundle load. See motor truck cargo insurance.
  • General liability for time spent on the facility's property, such as loading docks and yards.
  • The facility's exact legal name as certificate holder, and sometimes as additional insured.
  • Waiver of subrogation and notice before cancellation.

Terms that need the policy

Keeping requests in order

  • Keep one list of every certificate holder with the exact name, address, required limits and terms, and the date sent.
  • Send updated certificates to every holder at each renewal.
  • Keep each facility's written requirements so you can compare them with your policy before you haul.

A checklist

  1. Get each facility's insurance requirements in writing.
  2. Compare them with your policy and endorsements.
  3. Confirm the holder's exact legal name.
  4. Log every certificate sent.
  5. Reissue to all holders at renewal.

Securing steel on the trailer: flatbed cargo securement and steel coils.

Renewal time: a dedicated contract renewal checklist.

Dedicated accounts: a COI request checklist for dedicated accounts.

FAQ

Does a certificate of insurance add a plant to my policy?

No. A certificate shows what the policy says on the day it is issued. Adding a plant as an additional insured takes an endorsement on the policy.

What limits do mills and plants ask for?

It varies by facility and contract. The federal floor for for-hire freight vehicles rated 10,001 pounds or more is $750,000 (49 CFR 387.303T). Many facilities ask for more, plus cargo and general liability limits.

Can a plant check my federal filing itself?

Yes. FMCSA's public Licensing and Insurance system shows a carrier's authority and the insurance filings on record.

What is a waiver of subrogation on a certificate?

It means your insurer will not try to recover a claim payment from the plant. It only applies if the policy has that endorsement. The certificate just reports it.

How often do plants ask for new certificates?

At least at each policy renewal, and whenever a facility's requirements change or a new site is added. Keeping a list of every holder makes renewals faster.

Can a contract with a plant waive federal insurance rules?

No. Federal law lets parties waive some rights in a written contract, but not the rules on registration, insurance or safety fitness (49 USC 14101(b)).

This guide is general information, not advice on any policy.

Sources