Certificates of Insurance: What to Require and How to Read One
A subcontractor emails you a certificate of insurance the morning they mobilize. You glance at it, see the limits look about right, and file it.
That certificate almost certainly does not do what you think it does.
Here is what one actually is, what to require, which endorsements matter, and how to read the form line by line. It sits underneath subcontractor prequalification — verify insurance at prequalification, re-verify at every renewal.
What a certificate of insurance is, and what it is not
A certificate of insurance — nearly always the ACORD 25 form — is a one-page summary of policies that were in force on the day someone typed it up.
It is a snapshot, produced by an agent who does not control the policies and cannot change them. Read the disclaimer printed on the form itself. It says, in substance, that the certificate is issued as a matter of information only, confers no rights on the holder, does not amend or alter the coverage afforded by the policies, and that the policies themselves govern.
Courts across the country have generally enforced that disclaimer. A certificate showing you as an additional insured, with no endorsement behind it, will not reliably get you a defense when a claim lands. The policy governs, not the certificate.
Three consequences follow, and they shape everything else on this page:
- The certificate proves nothing about endorsements. Ticking a box marked "additional insured" is a clerical act, not a coverage grant.
- The certificate is downstream of the subcontract. If your subcontract does not require a coverage, no certificate creates the obligation.
- The certificate goes stale. It describes a moment. Policies get cancelled, limits get eroded, and nobody tells you.
So collect certificates — you have to — but treat them as a tracking artifact, not as proof of coverage. The proof is the endorsement forms and the subcontract.
The coverages to require
Requirements vary enormously by job size, owner, lender, trade and state. A $40,000 flooring sub on a tenant fit-out and a $4M mechanical sub on a hospital should not carry the same exhibit.
The ranges below are what you commonly see on commercial work. Treat them as a starting point for a conversation with your broker, not as a standard.
| Coverage | What it responds to | Common limit range |
|---|---|---|
| Commercial general liability | Bodily injury and property damage from operations and completed work | $1M–$2M per occurrence; $2M general aggregate |
| Products-completed operations aggregate | Damage arising from the sub's work after it is finished | Commonly $2M, separate from the general aggregate |
| Automobile liability | Owned, hired and non-owned vehicles | $1M combined single limit |
| Workers' compensation | Statutory injury benefits for the sub's employees | Statutory |
| Employers' liability | Injury claims outside the comp system | $500,000–$1M each accident / disease |
| Umbrella or excess liability | Sits above GL, auto and employers' liability | $1M–$25M depending on job size |
Scale the umbrella requirement to the job, not to the sub. Requiring $10M excess from a $75,000 sub prices them out for no benefit; requiring $1M from the steel erector on a high-rise is under-protected. This varies by owner and lender — many owners set it for you.
Coverages to add when the scope calls for them
Four more products come up regularly, and each is tied to a specific exposure rather than to job size.
| Coverage | Require it when |
|---|---|
| Professional liability | The sub performs design, delegated engineering, or design-build scope — fire protection layout, curtain wall, structural steel connections, MEP coordination drawings |
| Contractors pollution liability | The scope touches fuel, chemicals, abatement, dewatering, soil disturbance, or anything with a mould or silica exposure |
| Installation floater | The sub's materials are stored or in transit at meaningful value before installation |
| Builder's risk | Usually carried by the owner or GC for the project — confirm who buys it and whether subs are named insureds, rather than requiring it from each sub |
Whether your builder's risk names subcontractors as insureds changes who can sue whom after a fire. It is a five-minute question and it decides a seven-figure subrogation fight.
The endorsements that actually matter
This is what separates a compliance program that works from one that generates paper.
An endorsement is a form attached to the policy that changes what the policy does. The certificate may reference one, but only the endorsement itself grants coverage. Ask for the actual forms.
| Endorsement | What it does for you | Why the certificate box is not enough |
|---|---|---|
| Additional insured — ongoing operations | Extends the sub's GL to cover you for liability arising from their work while it is in progress | The box says "additional insured" without saying which form, which grant, or whether it was ever issued |
| Additional insured — products-completed operations | Extends that status to claims arising after the work is finished | A separate form. Subs routinely carry only the ongoing-operations version, and nobody notices until a claim arrives two years later |
| Primary and non-contributory | Puts the sub's policy first and stops it demanding contribution from yours | Without it, both carriers argue about order while your policy pays defense costs |
| Waiver of subrogation | Stops the sub's carrier from suing you after it pays a claim | Must be endorsed and usually must be required by written contract before the loss |
| Per-project aggregate | Gives the job its own aggregate limit instead of sharing one across the sub's whole year | Without it, three bad jobs elsewhere can exhaust the limits protecting yours |
| Notice of cancellation | Puts you in line to be told when the policy goes away | Modern ACORD wording promises notice "in accordance with the policy provisions" — which may mean the insured, not you |
The additional insured trap, stated plainly
Say it once more, because it is the most common expensive mistake in subcontractor compliance.
Ongoing operations and completed operations are two different endorsements. A sub can be entirely honest, entirely insured, and hand you a certificate with the additional insured box ticked while carrying only the ongoing-operations form. Your exposure from their work does not end at substantial completion — it arguably begins there.
Blanket additional insured endorsements — the kind that automatically cover "any person or organization you are required by written contract to add" — are common and generally fine, but they only trigger if the written contract requires it. Your subcontract has to say so, in writing, signed, before the loss.
Reading a certificate line by line
Work down the form in this order. Most defective certificates fail in the first two checks.
1. Named insured
The name in the insured box must match the entity that signed your subcontract, exactly.
This is a real trap and it is not pedantry. Contractors operate through DBAs, affiliates and holding companies with near-identical names, and the policy covers the named entity — not the one with the similar name that happens to be doing your work.
- "Smith Mechanical LLC" is not "Smith Mechanical Services Inc."
- "Smith Mechanical LLC dba SMS Plumbing" is fine if that DBA is on the policy
- A parent's policy does not automatically cover a subsidiary doing the work
If the names differ, resolve it before mobilization. Compare all three documents: subcontract, W-9, certificate.
2. Producer
The certificate should be issued by a licensed insurance agency or broker, with a name, address and contact details in the producer box.
A certificate that arrives as a PDF the subcontractor produced themselves — or one where the producer field is blank, generic, or an email address at the sub's own domain — is a stop. Call the producer directly using a number you look up, not the one printed on the document.
3. Insurers and A.M. Best ratings
The form lists each carrier by name and NAIC number in the "Insurer(s) Affording Coverage" block.
Many subcontracts require every carrier to be rated A- VII or better by A.M. Best — the letter is financial strength, the Roman numeral is size of surplus. If that is your requirement, check it; ratings are free to look up.
Also check whether a carrier is admitted in the state of the work. Non-admitted (surplus lines) carriers are legitimate and sometimes the only market for a hard trade, but they are not backed by the state guaranty fund, so their insolvency is your loss to absorb.
4. Policy numbers and dates
Every line of coverage needs a policy number and both effective and expiration dates.
Then do the arithmetic that nobody does: compare the expiration date to your schedule. A policy expiring in six weeks on a nine-month scope is not a problem today and is a certain problem later.
5. Limits
Compare each limit to your insurance exhibit, not to your memory.
Check the general aggregate and the products-completed operations aggregate separately — they are different lines on the form and subs are far more often short on the second.
6. Description of operations
This box should reference your project by name or number, and ideally recite the endorsement status you required. A box that says nothing, or names a different job, tells you the certificate was pulled from a drawer rather than issued for you.
7. Certificate holder
Your legal entity, spelled correctly, at an address where you receive mail. The holder box has almost no legal effect — it does not make you an additional insured — but it is how you land on the producer's renewal list, which is how next year's certificate arrives without chasing.
Products-completed operations: the exposure that outlives the job
When a sub finishes, their operations exposure ends and their completed operations exposure begins. That is the coverage that responds when the roof they installed leaks three years later. Two things follow, and both are administrative problems.
Require the coverage to be maintained after completion. Subcontracts commonly require completed operations coverage and additional insured status to be maintained for a stated number of years after substantial completion — often set to match the state's statute of repose for construction defect claims, which varies widely by state.
That means collecting certificates from subs who no longer work for you. A sub who finished three years ago has no commercial reason to send you anything, and the one thing that made them respond — payment — is gone.
Build the post-completion certificate requirement into the subcontract and into your tracking system on the day you write the subcontract, not on the day the job closes. The years vary by state; confirm the repose period for your jurisdiction with counsel.
Practical mitigations, best first:
- Retain a small final payment until the sub confirms in writing how completed operations coverage will be maintained
- Add the sub's producer as a contact so renewal certificates issue automatically
- Track post-completion certificate obligations in the same system as active ones, with the project closeout date as the trigger
The direct dollar cost: uninsured subcontractor charges
This is the section that gets budget approved for a tracking system, because it is not about risk. It is about a bill you will receive.
Your general liability and workers' compensation policies are auditable. At the end of the policy year the carrier audits your payroll and your subcontractor costs and adjusts the premium — and at that audit it asks for a certificate for every subcontractor you paid.
For any sub whose certificate you cannot produce, the carrier can treat that sub as uninsured and charge you additional premium as though the work were yours.
| Policy | How the uninsured sub is charged | Practical effect |
|---|---|---|
| General liability | The sub's contract cost is added to your rated exposure basis | You pay GL premium on their contract value |
| Workers' compensation | The sub's payroll — or, absent records, an assumed portion of contract value — is added to your payroll at your rate or the trade rate | Frequently the larger of the two charges |
The rules, classifications and rates vary by state and by carrier. What does not vary is the direction: missing certificates cost money at audit, every time.
Note that the charge turns on the certificate you can produce at audit time, not the one you once had — a certificate that expired mid-job and was never renewed leaves a chargeable gap. Getting it afterwards usually works, unless the sub has gone out of business.
Before your annual GL and comp audits, run a report of every sub paid during the policy year against your certificate file, and close the gaps first. The audit is the cheapest deadline in your compliance calendar to hit and the most expensive to miss.
The certificate is downstream of the subcontract
None of the above is enforceable because you asked for it. It is enforceable because the subcontract says so.
Your subcontract's insurance article — usually with an exhibit attached — is where coverages, limits, endorsements, post-completion periods, carrier ratings and the consequences of non-compliance live. A certificate is only evidence that the sub complied with that article.
Next to it sit the indemnity provision and the mutual waiver of subrogation. These interact with insurance in genuinely state-specific ways, and many states have anti-indemnity statutes that void or limit broad-form indemnity in construction contracts.
Do not draft or edit indemnity language from a template you found online, including this one. Have a construction attorney licensed in the state of the work write your insurance article and indemnity clause, and have your broker read them together. They have to agree with each other or your indemnity is uninsured.
You can generate a starting exhibit with the insurance requirements exhibit template, then have counsel and your broker finish it. See also contract insurance requirements and your own coverage.
The process that makes this work
Compliance programs fail on process, not knowledge. Four rules carry most of the weight.
Require the certificate before mobilization, never after. Every bit of your negotiating position exists before the sub is on site. After that, a deficient certificate becomes a fight about stopping production.
No certificate, no site access, no payment. Put it in the subcontract and the onboarding packet, then hold the line the first time. The first exception you grant becomes the standard.
Track expirations and act 30 days out. Chase the producer, not the sub — the producer can issue a renewal certificate in minutes.
Get renewals automatically. Being listed correctly in the certificate holder box puts you on the producer's renewal run, which eliminates most chasing.
See collecting and tracking certificates for the operating detail and the compliance tracker for a manual version you can run in a spreadsheet.
Red flags on a certificate
Any one of these means stop and resolve before the sub works.
| Red flag | What it usually means |
|---|---|
| Expiration date falls inside your schedule | Nothing yet — but a certain gap later. Diary it now |
| Limits below your exhibit | The sub bid the job without reading the insurance requirements, and the cost of compliance is about to become a change order request |
| Named insured does not match the subcontract entity | Either a clerical error or the wrong entity is doing the work. Both need resolving |
| No endorsement forms attached | You have a box ticked and no coverage grant. Ask for the forms |
| Additional insured with no completed operations form | The most common gap on this list, and the one that surfaces years later |
| Certificate issued by the subcontractor, not a licensed producer | Treat as unverified until the producer confirms it directly |
| Producer field blank, generic, or on the sub's own domain | Same. Verify by calling a number you look up yourself |
| Carrier not rated, below A- VII, or non-admitted in the state | May be acceptable, may violate the subcontract. Decide deliberately, not by default |
| Handwritten or visibly edited PDF | Certificates are system-generated. Alterations are a stop |
| Workers' comp shows an exclusion for officers with no employees listed | Common and often legitimate, but confirm who is actually swinging a hammer on your site |
| Description of operations references a different project | The certificate was recycled. Get one issued for your job |
What to do next
Building the requirement from scratch, start with the exhibit and have counsel and your broker review it before it goes into a subcontract. Inheriting a pile of certificates, run the audit-gap check first — that one has a deadline and a dollar figure attached.
Insurance lapsing for non-payment is also an early distress signal. See warning signs a subcontractor is in trouble.
Related Resources
- COI Collection & Tracking — expiry workflow
- Insurance Requirements Exhibit — merge-field exhibit
- Contract Insurance Requirements — prime contract flow-down
Not legal or insurance advice. Insurance requirements, anti-indemnity statutes, statutes of repose and audit rules vary by state and change. Have your construction attorney and your insurance broker review your subcontract insurance article and your certificate requirements before you use them.
Try it: Insurance Requirements Exhibit.