Written by Justin Goodman, CIC, CRIS, CCIP, CEO and Co-Founder, Total CSR
Published: August 3, 2026 · Last reviewed: August 3, 2026
In plain language: Additional insured status means a business or person gets added to someone else’s liability insurance policy. If a general contractor adds a subcontractor’s client as an additional insured, that client can access insurance coverage under the subcontractor’s policy if a lawsuit arises from the subcontractor’s work.
Technical definition (additional insured definition): Additional insured refers to a party granted coverage rights under another entity’s liability insurance policy, typically through an ISO insurance endorsement such as CG 20 10 or CG 20 37, extending protection for liability arising out of the named insured’s operations, products, or premises, subject to additional insured wording limitations.
Additional Insured at a Glance
| Attribute | Detail |
|---|---|
| Also known as | AI status, additional insured endorsement, secondary insured, additional named insured |
| Category | Liability policy endorsement |
| Lines of business | Commercial General Liability, Commercial Umbrella, Business Auto, commercial auto insurance |
| Industries most affected | Construction, real estate, property management, manufacturing |
| Related forms or endorsements | CG 20 10 (ongoing operations), CG 20 37 (completed operations), CG 20 33 (automatic status per contract), CG 20 26 (blanket, no products-completed operations) |
| Who bears the risk | The first named insured’s insurance carrier extends coverage; the additional insured relies on someone else’s policy |
| Common solution | Contractual requirements paired with the correct ISO additional insured endorsement |
| Also interacts with | Certificates of insurance, hold harmless agreements, hold harmless clause, primary and noncontributory wording, waiver of subrogation, loss payee, additional interest |
Key Takeaways
- Additional insured status gives a third party liability protection rights under another party’s policy, usually because a contract required it.
- Agencies handle additional insured requests constantly in construction, leasing, and vendor business relationships, making accuracy in endorsement selection a daily E&O concern.
- The most common pitfall is assuming a certificate of insurance alone proves insurance coverage exists, when only the actual insurance endorsement attached to the policy creates the legal right.
- A quick win is confirming which endorsement form is attached, since CG 20 10 and CG 20 37 cover different phases of work and using the wrong one leaves coverage gaps.
What Is Additional Insured in Insurance?
Additional insured is a status granted through an insurance endorsement attached to a general liability insurance policy, extending certain insurance coverage rights to a party that is not the first named insured. Contracts drive this requirement constantly: a property owner leasing to a tenant, a general contractor hiring a subcontractor, or a franchisor working with a franchisee will demand additional insured status to make sure they can access the other party’s coverage if a claim arises from that party’s work or premises.
The legal purpose behind additional insured status is risk transfer and protection against vicarious liability. Rather than relying solely on an indemnity agreement or hold harmless clause in a contract, which can be difficult and slow to enforce, the party seeking protection gets direct access to liability insurance and its defense obligations. Courts have generally supported this approach because it shifts the financial burden to the party actually creating the exposure, which aligns with how liability is allocated in the underlying business relationships.
Consider a general contractor building a retail center on construction projects. The GC requires its framing subcontractor to add the GC as an additional insured on the subcontractor’s CGL policy using CG 20 10. A worker on the framing crew falls and sues the property owner and the GC, alleging inadequate site safety and bodily injury. Because the GC holds additional insured status under the subcontractor’s policy, the subcontractor’s insurance carrier may owe the GC a legal defense and indemnity, separate from whatever the GC’s own policy provides.
Additional insured status is not unlimited. Additional insurance coverage only extends to liability “arising out of” the named insured’s work, product, or premises as defined in the specific additional insured language, and it does not make the additional insured a co-owner of the entire policy or responsible for premium payments.
How Does Additional Insured Work?
- The contract requirement. A written agreement between two business partners, such as a lease or subcontract, requires one party to name the other as an additional insured on its liability insurance policy to meet insurance requirements.
- The endorsement request. The named insured’s insurance agent or licensed insurance agent requests the appropriate ISO additional insured endorsement from the insurance carrier, matching the contractual requirements to the correct form, such as CG 20 10 for ongoing operations or CG 20 37 for completed operations, after review by underwriting departments.
- The certificate issuance. The agency issues a certificate of insurance reflecting the additional insured status, though the certificate itself is only evidence and does not create insurance coverage.
- The triggering loss. A third party suffers bodily injury or property damage in connection with the named insured’s work, product, or premises covered under the endorsement’s coverage scope.
- The tender and response. The additional insured tenders the claim to the named insured’s insurance carrier, which investigates whether the loss falls within the additional insured wording and policy terms before agreeing to defend or indemnify, considering coverage limits and defense costs.
Real Claim Examples Involving Additional Insured
Scaffolding Collapse During Building Renovation
A commercial building owner hired a general contractor to renovate an office building and required additional insured status via CG 20 10 on the GC’s general liability insurance policy. During the project, scaffolding erected by the GC’s crew collapsed, causing bodily injury to a pedestrian who then sued both the GC and the property owner for property damage and medical expenses. Because the endorsement covered ongoing operations, the property owner tendered the claim to the GC’s insurance carrier and received a defense, avoiding a direct hit to the owner’s own commercial property insurance policy and preventing increased insurance costs.
Completed Roofing Job With a Later Leak
A property management company required its roofing contractor to name it as an additional insured, but the contractor’s insurance agent only attached CG 20 10, which covers ongoing operations, not CG 20 37 for completed operations. Two years after the roof was finished, a leak caused water damage and the tenant sued the property manager. The roofing contractor’s insurance carrier denied the tender because the loss occurred after the work was completed and the wrong endorsement was in place, leaving the property manager without additional insured protection for that claim and exposing coverage gaps in their liability protection.
Leased Retail Space Slip and Fall
A retail tenant’s lease required the tenant to add the landlord as an additional insured using a blanket additional insured endorsement tied to the lease agreement. A customer slipped on a wet floor inside the leased space and sued the landlord along with the tenant for bodily injury. Because the endorsement was blanket and automatically triggered by the lease requirement, the landlord’s status was confirmed without needing a separate endorsement request, and the tenant’s insurance carrier accepted the tender, covering defense costs and potential claim payments within policy limits.
Additional Insured vs. Certificate Holder: What Is the Difference?
Additional insured status and certificate holder status are frequently confused because both appear on the same certificate of insurance document. Additional insured is a contractual insurance coverage right created by an insurance endorsement on the policy, while certificate holder simply identifies who receives a copy of the certificate for informational purposes. Neither should be confused with additional interest or loss payee designations, which serve different functions in property insurance and vehicle insurance contexts.
| Comparison area | Additional Insured | Certificate Holder |
|---|---|---|
| Primary use case | Granting liability protection rights to a third party | Identifying who receives the certificate document |
| Coverage / concept type | Substantive endorsement changing policy coverage | Administrative label with no coverage effect |
| Typical exclusions | Limited to liability arising from named insureds’ work, product, or premises | Not applicable, no insurance coverage is created |
| Who is most affected by errors | Third party assuming insurance coverage exists without the endorsement | Party who mistakenly believes certificate holder status equals liability protection |
| Common mistakes | Wrong endorsement form attached, or coverage scope too narrow for the contract | Assuming being listed as certificate holder provides any legal protection or lawsuit protection |
What Are the Most Common Mistakes With Additional Insured?
- Treating a certificate of insurance as proof of insurance coverage, when only the actual insurance endorsement attached to the policy creates legal rights, leaving the additional insured exposed if the endorsement was never issued by insurance companies.
- Using CG 20 10 alone when the contract or exposure requires completed operations coverage, creating coverage gaps for claims arising after the project finishes since CG 20 10 by itself, in its current edition, does not cover completed operations or product liability exposures.
- Failing to match additional insured wording to contract language, so the additional insured’s actual exposure is broader than what the endorsement covers, leaving potential court fees and judgment costs unprotected.
- Assuming additional insured status includes primary and noncontributory wording automatically, when that liability protection requires separate policy language or endorsement to prevent contribution from the additional insured’s own policy limits.
- Not confirming that the insurance endorsement remains in force for the full duration of the business relationships, especially on multi-year leases or long-tail construction defect exposures, and failing to track policy renewal dates.
- Relying on a producer’s verbal assurance instead of confirming the endorsement in writing with the insurance carrier before work begins, which creates unsupported E&O exposure if a dispute arises later and affects loss history.
- Overlooking independent negligence exclusions in additional insured language that may limit coverage when the additional insured’s own actions contribute to the loss.
How to Explain Additional Insured to a Client
Explaining Additional Insured to a personal lines client
Additional insured status usually comes up for personal lines clients when a landlord requires it for a rental property or when a mortgage lender needs to be listed for a certain interest as a loss payee. Think of it as your liability insurance extending a form of protection to another party because of a specific relationship, like a lease, without making them the owner of your policy or responsible for your premium payments.
Explaining Additional Insured to a small business owner
Additional insured status means another business, like a property owner or general contractor you work with, gets added to your general liability insurance policy because your contract requires it. If something goes wrong connected to your work on their construction projects or at their location, their claim for property damage or bodily injury can be directed to your insurance carrier instead of only relying on the contract’s hold harmless clause to cover them. Your insurance agent can help ensure the right insurance endorsement is in place to meet insurance requirements without unnecessary insurance costs.
Explaining Additional Insured to a CFO or risk manager
Additional insured endorsements are how we convert contractual risk transfer language into an enforceable insurance mechanism rather than relying purely on indemnity agreement clauses. We need to confirm which ISO endorsement form is attached, whether it covers both ongoing and completed operations, and whether primary and noncontributory wording is included, because each of those variables changes how a claim will actually respond in terms of defense costs, coverage limits, and claim payments. We must also verify the additional insured language addresses vicarious liability exposures and that policy declarations accurately reflect all named insureds and their coverage scope to avoid coverage gaps that could impact our loss history and future insurance costs.
Frequently Asked Questions About Additional Insured
Does a certificate of insurance prove additional insured status?
A certificate of insurance does not by itself prove additional insured status exists. The certificate is an informational document, and insurance coverage only exists if the actual policy endorsement, such as CG 20 10 or CG 20 37, has been issued and attached to the named insured’s policy by the insurance carrier.
What is the difference between CG 20 10 and CG 20 37?
CG 20 10 grants additional insured status for liability arising from the named insured’s ongoing operations, while CG 20 37 extends that status to the products-completed operations hazard after the work is finished. Many contracts, especially in construction projects, require both forms together to cover the full lifecycle of a project and prevent coverage gaps that could leave property damage or bodily injury claims unprotected.
Can additional insured status be added automatically without a specific request?
Additional insured status can be added automatically through a blanket insurance endorsement, such as CG 20 33 or CG 20 26, which extends insurance coverage to any party the named insured is required to add under a written contract. This approach reduces the risk of missed individual endorsement requests but still requires confirming the endorsement itself is on the policy and meets contractual requirements.
Does additional insured status make the third party a named insured?
Additional insured status does not make the third party a first named insured on the policy. The additional insured typically has narrower rights limited to the specific liability arising from the named insured’s work, product, or premises per the additional insured wording, and does not control policy decisions like cancellation or policy renewal, nor are they responsible for premium payments.
Why would a claim be denied even with an additional insured endorsement in place?
A claim can be denied even with an endorsement in place if the loss falls outside the endorsement’s specific coverage scope, such as a completed operations claim under a policy that only has CG 20 10 for ongoing operations. Denials also occur when the loss is not actually connected to the named insured’s work, product, or premises as required by the additional insured language, or when independent negligence by the additional insured is the sole cause, leaving defense costs and judgment costs unpaid.
Is primary and noncontributory wording the same as additional insured status?
Primary and noncontributory wording is not the same as additional insured status, though the two are often required together in contracts. Additional insured status grants liability protection rights, while primary and noncontributory wording determines the order in which that insurance coverage responds relative to the additional insured’s own policy limits and prevents sharing of claim payments between insurance companies.
Related Insurance Terms
- Certificate of Insurance: a document summarizing policy coverage that is often mistaken for proof of additional insured status, though it carries no contractual insurance coverage guarantee on its own.
- Hold Harmless Agreement: a contract clause requiring one party to indemnify another, frequently paired with additional insured requirements to transfer risk through both contract and insurance mechanisms, also known as a hold harmless clause.
- Primary and Noncontributory: policy wording that determines whether the named insured’s insurance coverage responds first, often required alongside additional insured status to prevent the additional insured’s own policy limits from sharing the loss or defense costs.
- Waiver of Subrogation: an insurance endorsement preventing an insurance carrier from pursuing recovery against a specific party, commonly requested in the same contracts that require additional insured status.
- Named Insured: the primary policyholder whose general liability insurance policy an additional insured is added to, holding broader rights and obligations than the additional insured party, including control over policy renewal and premium payments.
- Professional Liability Insurance: coverage for errors and omissions in professional services, which typically does not extend additional insured status but may interact with general liability insurance in complex business relationships.
- Commercial Auto Insurance: vehicle insurance that may include additional insured provisions when heavy equipment or vehicles are used on construction projects or in business operations.
Sources and References
- Insurance Services Office (ISO), referenced via IRMI. Additional Insured.
- International Risk Management Institute (IRMI). Additional Insured Endorsements: A Guide.
About the Author
Justin Goodman, CIC, CCIP, CISC, CLCS, CRIS, PCIA, QCLS, MFHR
CEO and Co-Founder, Total CSR, Inc.
Justin Goodman is a third-generation insurance broker with over two decades in agency operations. He has trained more than 50,000 CSRs, account managers, and producers in commercial and personal lines coverage, from workers’ compensation to construction risk. He was named 2024 Insurance Journal Agent of the Year and one of the nation’s top five construction insurance experts by Risk & Insurance. He is the author of Retain, which applies cognitive science research on memory and knowledge transfer to insurance training, and speaks nationally on how agencies build durable technical expertise in their teams.