What is a certificate of insurance (COI)?

Sooner or later, every business that hires carriers — or is asked to let one onto its property — runs into the request: “send us your COI.” A certificate of insurance is one of the most-exchanged documents in commercial freight, and one of the least understood. It takes about a minute to read once you know what you’re looking at, and knowing what it can and can’t tell you is the difference between real verification and paperwork theatre.

The definition, in plain terms

A certificate of insurance is a standardized summary document, issued by an insurance broker or insurer, stating that a named company holds specific insurance policies as of the issue date. A typical carrier COI shows:

• The named insured — the company that holds the policies.
• The insurer(s) — which insurance companies wrote the coverage.
• Types of coverage — for a carrier, usually commercial general liability, automobile liability, and cargo coverage.
• Coverage limits — the maximum each policy pays.
• Policy numbers and the policy period — the dates coverage is in force.
• The certificate holder — the party the certificate was issued to, usually the customer or property owner who requested it.

The document exists to answer one question quickly: does this company actually carry the insurance it claims to carry, right now? Because the certificate comes from the broker rather than the carrier itself, it’s meaningfully harder to fake than a verbal assurance — which is why sophisticated shippers treat “can you send a COI?” as a standard vetting step, right alongside the other questions to ask a new carrier.

Why businesses request COIs from carriers

The requests come from a few directions, all rational:

Shippers vetting a carrier. Before freight moves, a shipper wants evidence that cargo coverage exists and that liability insurance would respond if a driver damaged property or injured someone during a delivery. What coverage types and limits to look for is its own topic — our answer on what insurance a carrier should have breaks it down.

Property managers and facilities. Warehouses, office campuses, construction sites and retail properties routinely require a COI before a commercial vehicle operates on site. If a truck damages a dock door or a person, the property owner wants a well-insured party on the other side of the incident.

Contracts and vendor onboarding. Many B2B service agreements specify minimum insurance limits and require a certificate as proof before work starts, with renewal certificates collected annually. Larger shippers fold the COI into a vendor file alongside a WSIB clearance certificate — see WSIB clearance and carrier requirements for why those two documents travel together in Ontario.

The pattern across all three: the COI shifts the conversation from trust to evidence. Anyone can say “we’re fully insured.” The certificate makes the claim checkable.

The request also runs in both directions. A carrier asked for a COI by a new customer or property manager treats it as routine — the broker issues certificates constantly, and turnaround is usually quick. If a carrier acts like the request is unusual or intrusive, that reaction is itself information: professional operations exchange this document weekly and have the process down cold.

What a COI is not

This is where careful readers separate from casual ones. A certificate of insurance:

• Is not the policy. The policy’s full terms, conditions and exclusions govern what’s actually covered; the certificate is a summary and typically says so on its face.
• Does not modify coverage. Being handed a COI, or even being listed as certificate holder, doesn’t extend the policy’s protection to you. That requires an endorsement on the policy itself.
• Is a snapshot, not a promise. It reflects coverage as of the issue date. Policies can be cancelled or altered afterwards, which is why currency matters and why recurring relationships re-collect certificates at renewal.
• Doesn’t tell you whether a specific loss would be paid. Exclusions, deductibles and conditions live in the policy wording. For freight specifically, whether cargo coverage responds to a given loss depends on those terms — our answer on whether freight is insured in transit explains how carrier liability and cargo insurance interact.

None of this makes the COI weak — it makes it exactly what it is: an efficient screening document. It reliably filters out carriers with no coverage or lapsed coverage, which is most of what a shipper needs it to do.

How to read one in sixty seconds

When a certificate lands in your inbox, check five things:

1. Named insured matches the company you’re hiring — exactly, not a similar name or a numbered company you’ve never heard of.
2. Policy dates cover today and reach comfortably past your shipment or contract period.
3. The coverage types you care about are present — for freight, that includes cargo coverage, not just general liability.
4. Limits meet your requirement — whatever your contract or risk tolerance specifies.
5. It came from a broker or insurer, with contact details you could call to verify if the stakes warrant it.

Anything off — expired dates, a mismatched name, missing cargo coverage, or delay and excuses in producing the document at all — is a signal worth taking seriously. For the fuller picture of what certificates reveal about an operation, see carrier insurance certificates explained.

Sonic Transport works with GTA and Southern Ontario businesses that take vendor vetting seriously — it’s a normal part of professional B2B freight, and we’d rather work with shippers who check. If you’re setting up a carrier for same-day direct or recurring work, tell us about your freight and your requirements and a real person will follow up.