Why It Matters
Landlords and investors use COIs as proof that a contractor, tenant, or vendor carries adequate insurance before allowing them access to a property. The document lists policy numbers, effective dates, coverage limits, and can name you as an "additional insured" — meaning their policy extends a layer of protection to you if a claim arises from their work. Requesting a COI before a tenant signs a lease, before a roofer steps on your property, or before handing keys to a property manager is standard risk management practice. It costs nothing to request and can save you from absorbing liability that belongs on someone else's policy. Understanding what a COI contains is as important as knowing when to ask for one.
At a Glance
- Summarizes coverage type, policy limits, effective dates, and insurer name on a single page
- Does not replace the actual insurance policy — it is proof of coverage, not the contract itself
- Can be amended to name you as an additional insured, extending the policy's protection to you
- Issued by the insurance company or its authorized agent, not by the insured party
- Typically valid for one year and must be renewed when the underlying policy renews
How It Works
A COI is issued by the insurer, not the policyholder. When a contractor says "I'm insured," that's a statement — when they hand you a COI, that's documentation. The insurer (or their authorized agent) produces the document directly, which means the information on it reflects what the insurer actually knows. Certificates are standardized using the ACORD 25 form in the U.S., so every legitimate COI looks roughly the same regardless of carrier.
The additional insured designation is the most important line item for property owners. When you're named as an additional insured on a contractor's commercial property insurance or general liability policy, you gain standing to file a claim directly against their coverage if their work causes damage or injury at your property. Without this designation, you would need to pursue the contractor personally, which is slower and less certain. Always request additional insured status in writing before work begins — not after the fact.
COIs expire when the underlying policy does, which means you need to track renewals. A COI dated January through December is worthless in February of the following year if the contractor let coverage lapse. For long-term contractors or property managers who work on your properties regularly, set a calendar reminder to request a fresh COI at each policy renewal. If a vendor goes uninsured mid-project, you may not find out until a claim surfaces — at which point the exposure lands on your policy. This is especially critical if you carry vacant property insurance during turnover periods or rely on business interruption coverage to replace lost rent — an uninsured vendor's negligence can trigger claims against those policies directly.
Real-World Example
Omar owns a 12-unit apartment building in Columbus, Ohio and hired a plumbing company to repipe two units — a $14,000 job. Before signing the contract, he asked for a COI showing general liability coverage of at least $1 million per occurrence and requested that his LLC be named as an additional insured. The plumbing company's insurer issued the certificate within 24 hours.
Three weeks into the project, a cracked fitting flooded the unit below, causing $8,400 in water damage to flooring, drywall, and a tenant's personal property. Because Omar was named as an additional insured, his attorney confirmed he had direct standing under the plumber's policy. The plumber's insurer covered the full structural repair. The tenant's renters insurance covered the damaged furniture. Omar's own policy wasn't touched — and his premium stayed flat at renewal. The $0 cost of requesting that COI saved him a $8,400 claim and a likely rate increase.
Pros & Cons
- Provides documented proof of coverage before risk exposure begins
- Naming yourself as additional insured creates a direct claim path against the contractor's policy
- Standardized ACORD format makes it easy to review and compare across vendors
- Protects your own policy from absorbing claims that belong to contractors or tenants
- Quick to obtain — most insurers issue certificates within one business day
- A COI only reflects coverage at the time it was issued — policies can lapse or be cancelled afterward
- Additional insured status varies by endorsement; some policies limit it significantly
- Does not replace reviewing the full policy for exclusions that may undermine the coverage shown
- Tenants and contractors sometimes provide fraudulent or outdated certificates — verification with the insurer is the only true safeguard
- Tracking renewals across multiple vendors requires active management and adds operational overhead
Watch Out
A COI is a snapshot, not a guarantee. The document proves the policy existed on the date it was issued — it does not guarantee coverage will remain in force through the project or lease term. Policies get cancelled for non-payment, policy violations, or business closures. For high-value projects or long-term contractors, consider asking the insurer to send you a cancellation notice directly. Some additional insured endorsements include this provision automatically — ask for it explicitly.
"Additional insured" language is not universal. Some policies restrict additional insured coverage to ongoing operations only, meaning coverage ends once the contractor finishes the job. If a builder's risk insurance claim surfaces six months after a renovation wraps up, the completed-operations exclusion may block your claim. Ask your attorney to review the actual endorsement — not just the certificate — before signing off on a major project.
A missing COI is a red flag, not a paperwork inconvenience. A legitimate, well-run contractor or property manager will have their COI ready before you ask. Pushback, delays, or vague promises of "I'll get that to you soon" often signal that coverage is thin, lapsed, or nonexistent. The same logic applies to tenants in states or markets where renters insurance is required as a lease condition. If a vendor can't produce a COI within 48 hours, treat it as a serious due diligence concern — not a bureaucratic hurdle.
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The Takeaway
A certificate of insurance is one of the lowest-effort, highest-return risk management tools available to a property investor. Requesting a COI before every contractor engagement, lease signing, and vendor relationship costs nothing and creates a paper trail that can redirect tens of thousands of dollars in liability away from your portfolio. Request additional insured status every time. Track expirations. Verify with the insurer when the stakes are high. It takes ten minutes and can save you from absorbing someone else's negligence.