Certificate of Insurance Documents: A Complete Guide

Certificate of insurance documents aren't just pieces of paper that vendors email you before they start work. They're the primary evidence that your vendors, tenants, and contractors carry active, compliant insurance coverage — and they're the first line of defense when something goes wrong on your property.

But navigating the different COI document types — ACORD 25, ACORD 27, ACORD 28, additional insured endorsements, waivers of subrogation — is confusing even for experienced property managers and compliance officers. Each form serves a different purpose, contains different information, and is required in different situations.

This guide covers every COI document type you're likely to encounter, what each one means, when you need it, and how to verify it's correct.

What Are COI Documents?

Certificate of insurance documents are standardized forms that summarize a party's insurance coverage. Their purpose is to provide a quick, verifiable snapshot of what insurance policies are in force — who is insured, what types of coverage they carry, what the policy limits are, and when the policies expire.

COI documents serve three critical functions in risk management:

1. Verification. They confirm that a vendor, tenant, or contractor actually carries the insurance they claim to have — before they start work or take possession of your property.
2. Notification. They establish your organization as the certificate holder, which in most cases entitles you to receive notice if a policy is cancelled or materially changed.
3. Documentation. They create a paper trail showing you performed due diligence in verifying insurance coverage — essential for insurance audits, lender requirements, and legal defense.

The insurance industry uses standardized forms developed and maintained by ACORD (Association for Cooperative Operations Research and Development) to ensure consistency across carriers, agents, and certificate holders. The three primary ACORD forms you'll encounter are the ACORD 25, ACORD 27, and ACORD 28 — plus a range of endorsements that modify the underlying policies.

ACORD 25 — Certificate of Liability Insurance

The ACORD 25 is the most common certificate of insurance document. It's the form you'll see in your inbox 95% of the time when you request proof of insurance from a vendor, contractor, or tenant.

The ACORD 25 summarizes liability insurance coverage — general liability, automobile liability, umbrella/excess liability, and workers' compensation. It also includes a section for "other" coverages like pollution liability or professional liability.

What the ACORD 25 Shows

• Producer information. The insurance agent or broker who issued the certificate — your point of contact if coverage needs to be revised or clarified.
• Insured information. The vendor or contractor's legal business name and mailing address. This must match the name on their contract and W-9.
• Insurer(s) affording coverage. Each insurance company providing coverage, identified by a letter (Insurer A, Insurer B, etc.) that maps to specific coverage types below.
• Coverage types and limits. The core of the form — each type of coverage the vendor carries, with policy numbers, effective dates, expiration dates, and per-occurrence and aggregate limits. General liability, auto liability, umbrella/excess, and workers' compensation each have their own row.
• Description of operations. A free-text field where endorsements are noted — additional insured status, waiver of subrogation, project-specific references, and primary/non-contributory language.
• Certificate holder. Your organization's legal name and address. This is who the certificate was issued to.
• Cancellation notice. A statement confirming you'll receive written notice if any listed policy is cancelled before its expiration date.
• Authorized representative signature. The form must be signed by the producer or their authorized representative to be valid.

How to Read an ACORD 25

When you receive an ACORD 25, verify these items in order: the insured name matches the vendor's legal name, the certificate holder is your correct organization and address, all required coverage types are checked (general liability at minimum), coverage limits meet your requirements, the policy is currently active (check effective and expiration dates), the additional insured endorsement is noted in the Description of Operations, and the form is signed and dated.

For a detailed, section-by-section walkthrough of every field on the ACORD 25 form, see our ACORD 25 guide.

ACORD 27 — Evidence of Property Insurance

The ACORD 27 is the evidence of property insurance form. While the ACORD 25 covers liability, the ACORD 27 covers physical assets — buildings, business personal property, equipment, inventory, and business income.

When You Need an ACORD 27

You typically need an ACORD 27 in these situations:

• Commercial tenants. When a tenant leases space in your building and is required to carry property insurance on their improvements, fixtures, equipment, or inventory. The ACORD 27 proves they have adequate coverage for their owned property.
• Lenders and mortgage holders. Commercial mortgage lenders frequently require evidence that the borrower maintains property insurance on the financed building. The ACORD 27 serves as that evidence.
• Contractors storing equipment on site. If a general contractor or subcontractor stores tools, materials, or equipment on your property, you may require proof they carry property insurance covering those items — especially if a loss could delay the project.
• Builders risk coverage. During construction or renovation projects, the ACORD 27 may be used to evidence builders risk insurance covering materials, equipment, and work in progress.

What the ACORD 27 Shows

The ACORD 27 documents property coverage including buildings, business personal property, business income and extra expense, equipment breakdown, and other property-related coverages. It lists perils insured against (typically "special form" covering all risks except those specifically excluded), coverage limits, deductibles, and any special conditions or exclusions.

For standard vendor COI tracking, you rarely need the ACORD 27 — the ACORD 25 covers liability, which is the primary concern when vendors are performing work on your property. However, commercial real estate managers and those dealing with tenants or contractors who store significant assets on site should be familiar with this form.

ACORD 28 — Evidence of Commercial Property Insurance

The ACORD 28 is similar to the ACORD 27 but provides more detailed information about commercial property coverage. It's typically used for larger commercial properties, multi-location coverage, and complex property insurance programs.

ACORD 27 vs ACORD 28 — What's the Difference?

Both forms evidence property insurance, but they serve different levels of complexity:

In practice, if you're requesting evidence of property insurance from a tenant or contractor and they provide an ACORD 28 instead of an ACORD 27, it's functionally equivalent — just more detailed. Accept either form as long as it shows the coverage types and limits you require.

Additional Insured Endorsements

An additional insured endorsement is arguably the most important COI-related document you'll handle — and the one most frequently overlooked.

What Is an Additional Insured Endorsement?

An additional insured endorsement is a formal amendment to a vendor's insurance policy that extends coverage to your organization. It means that if a claim arises from the vendor's work, your organization is covered under the vendor's policy — not just the vendor themselves. Without this endorsement, the vendor's insurance only protects the vendor. With it, you share in the protection.

The endorsement is a separate document from the ACORD 25. The ACORD 25 may mention additional insured status in the Description of Operations section, but that mention alone does not legally extend coverage. You need the actual endorsement form.

Common Additional Insured Endorsement Forms

• CG 2010 (07/04 or 11/85). The most common additional insured endorsement for general liability policies. It extends coverage to a person or organization when required by written contract. The 07/04 edition provides broader coverage than the 11/85 edition — it covers both ongoing and completed operations, while the older 11/85 version only covers ongoing operations.
• CG 2010 (04/13). A newer, narrower version of CG 2010. Coverage is limited to liability caused "in whole or in part" by the named insured's acts or omissions. Some property managers prefer the broader 07/04 version when available.
• CG 2037 (07/04). An additional insured endorsement specifically for owners, lessees, or contractors — used when the additional insured is the property owner or general contractor rather than a third party. Covers liability arising from the named insured's ongoing operations.
• CG 2033 (07/04). Additional insured endorsement for a designated person or organization — a broader form that can name any entity as additional insured, not limited to owners/lessees/contractors.

When you request a COI from a vendor, always specify: "Please provide an ACORD 25 with CG 2010 (07/04) additional insured endorsement naming [Your Organization's Legal Name]." The specific form edition matters — older forms often provide broader coverage.

How to Verify an Additional Insured Endorsement

When you receive an additional insured endorsement, verify: your organization's legal name is spelled correctly (an incorrect name can void coverage), the endorsement form number matches what you requested (CG 2010 vs CG 2037), the policy number on the endorsement matches the policy number on the ACORD 25, and the endorsement is signed and dated by the insurer.

Waiver of Subrogation

A waiver of subrogation is an endorsement that prevents the vendor's insurance company from pursuing your organization for reimbursement after paying a claim — even if your organization was partly at fault.

What Is Subrogation?

Subrogation is the legal right of an insurance company to "step into the shoes" of its insured after paying a claim, and pursue recovery from a third party who caused (or contributed to) the loss. For example: a vendor's employee is injured on your property due to a hazard you should have fixed. The vendor's workers' compensation insurer pays the claim, then sues your organization to recover the cost. Subrogation makes that possible.

Why You Need a Waiver of Subrogation

A waiver of subrogation blocks the vendor's insurer from suing you after paying a claim. It's a standard requirement in most commercial construction contracts, vendor agreements, and commercial leases. Without it, you could face a lawsuit from the vendor's insurance company years after the vendor finished work on your property, which your own insurance may or may not cover.

Common Waiver of Subrogation Forms

• CG 2404. Waiver of transfer of rights of recovery against others (waiver of subrogation) for general liability policies. This is the most common form.
• WC 000313. Waiver of our right to recover from others endorsement for workers' compensation policies. Blocks the workers' comp insurer from subrogating against you for workplace injuries.

The waiver of subrogation should be noted in the Description of Operations section of the ACORD 25, and you should request a copy of the endorsement itself from the vendor's insurance agent.

COI Document Checklist for Property Managers

Use this checklist every time you onboard a new vendor or renew an existing vendor's COI:

1. ACORD 25 — Certificate of Liability Insurance. Signed, dated, with all required coverage types checked, limits meeting your requirements, and your organization listed as certificate holder.
2. Additional Insured Endorsement. Copy of the actual endorsement (typically CG 2010 or CG 2037) with your organization's correct legal name.
3. Waiver of Subrogation Endorsement. If required by your contract (typically CG 2404 for general liability, WC 000313 for workers' comp).
4. Primary and Non-Contributory Language. Stated in the Description of Operations on the ACORD 25, confirming the vendor's insurance is primary and won't seek contribution from your policy.
5. ACORD 27 or ACORD 28. Only if you require evidence of the vendor's property insurance (equipment, inventory, builders risk). Not needed for standard liability verification.
6. Policy Declarations Pages. Optional but recommended for high-risk vendors — the declarations page shows the full policy terms, not just the summary on the ACORD 25.
7. Verification with Insurer. For high-value contracts or high-risk vendors, call the insurance agent listed on the ACORD 25 to confirm coverage is active and the certificate hasn't been altered.

Frequently Asked Questions

Industry Sources

• ACORD — Official provider of ACORD 25, ACORD 27, ACORD 28, and all standard insurance forms. acord.org
• International Risk Management Institute (IRMI) — Definitive resource on additional insured endorsements, contractual risk transfer, and COI verification best practices. irmi.com
• National Association of Insurance Commissioners (NAIC) — Regulatory guidance on certificate of insurance standards and state-specific requirements. content.naic.org
• Insurance Services Office (ISO) — Publisher of standard insurance policy forms including CG 2010, CG 2037, CG 2404, and WC 000313 endorsements. verisk.com

Related Resources

• Certificate of Insurance: The Complete Guide — everything about what COIs are, how they work, and why they matter
• ACORD 25 Guide — detailed, section-by-section walkthrough of the standard certificate of liability insurance
• COI Compliance Guide — how to define insurance requirements and enforce compliance across your portfolio
• Free ACORD Templates — downloadable fillable ACORD 25, ACORD 27, and ACORD 28 forms
• COI Tracking Software — automate COI document management, expiration alerts, and compliance reporting