Additional Insured on Professional Liability: Complete Guide (2026)

Quick Answer:

An additional insured endorsement extends your professional liability coverage to a third party (client, vendor, or landlord) for claims arising from your work. This is commonly required in client contracts, subcontracting agreements, and commercial leases.

Key Facts:

Cost: $0-$50 per certificate (varies by carrier)
Turnaround: 24-48 hours typical
Both Hartford and Chubb offer additional insured endorsements
Required information: Entity name, project details, policy period

If you've ever signed a client contract requiring you to "add them as an additional insured" to your professional liability policy, you're not alone. This common contract requirement protects clients from liability related to your professional services - but many consultants, contractors, and service providers don't fully understand what it means or how to request it.

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What is Additional Insured on Professional Liability?

An additional insured is a person or entity added to your professional liability insurance policy to receive coverage for claims arising from your work. Unlike the named insured (you or your business), an additional insured only has coverage related to your specific services or project.

How it differs from named insured:

The named insured is the primary policyholder - your business receives full coverage under the policy for all professional activities. An additional insured only receives coverage for claims related to your work performed for them.

For example, if you're an IT consultant working for a retail chain, adding them as an additional insured protects them from liability if your security recommendations lead to a data breach. The coverage only applies to claims arising from your specific consulting work.

Why clients and vendors require it:

Businesses require additional insured status to transfer some of their liability risk. If they're sued because of your professional advice or services, your professional liability policy responds first before their own coverage kicks in. This protects their insurance rates and limits from being impacted by claims related to your work.

When You Need Additional Insured Coverage

Additional insured requirements appear in several common business situations:

Client contract requirements:
Professional services contracts frequently require you to add the client as an additional insured. This is standard in consulting agreements, especially for projects involving significant risk exposure (IT security, financial advice, engineering design).

Subcontractor agreements:
When you subcontract to a larger firm, they typically require additional insured status. The prime contractor wants protection if they're sued for work you performed as their subcontractor.

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Vendor and supplier relationships:
Some enterprise software or service agreements require vendors to add the purchasing company as an additional insured, particularly for mission-critical systems or professional services.

Event and venue requirements:
Professional service providers working at events (speakers, trainers, consultants) may need to add the venue or event organizer as additional insured.

Landlord requirements:
Commercial landlords sometimes require tenants providing professional services to add them as additional insured on professional liability policies, especially if you see clients at your office location.

Who Typically Needs Additional Insured Endorsements

Consultants:

IT consultants and cybersecurity advisors
Management consultants
Strategy consultants
Business process consultants
Compliance consultants

Professional services:

Accountants and CPAs (especially for audit and advisory work)
Lawyers (when working as contract or subcontract counsel)
Engineers (on collaborative projects)
Architects (when working under prime design firms)

Contractors and subcontractors:
Design-build contractors and specialized trade contractors who provide professional design services or recommendations may need both general liability and professional liability additional insured endorsements.

Event vendors:
Professional speakers, trainers, facilitators, and coaches working at corporate events or conferences.

Software developers:
Developers and SaaS providers working on enterprise contracts, especially for custom development or integration projects where errors could create significant client liability.

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How to Request Additional Insured from Your Carrier

The process varies slightly by insurance carrier, but the general workflow is similar:

Hartford process:

Log into your Hartford online portal or contact your agent
Request an additional insured endorsement for your professional liability policy
Provide the required information (see below)
Receive certificate within 24-48 hours
Hartford typically processes these requests quickly through their online system

Chubb process:

Contact your Chubb agent or broker (Chubb doesn't offer direct online requests for professional liability additional insured)
Submit the additional insured request with complete details
Chubb underwriters review the request (especially for high-limit policies)
Receive endorsement and certificate within 24-48 hours for straightforward requests
More complex projects may require additional underwriting time

Required information:

Full legal name of the entity to be added
Address of the additional insured
Project description or scope of work
Policy period (ongoing or specific project dates)
Certificate holder information (where to send the certificate)

Typical turnaround time:
Most carriers issue additional insured endorsements within 24-48 hours for standard requests. Rush requests may be available for an additional fee. Plan ahead - don't wait until the contract signing deadline to request your endorsement.

Cost Breakdown for Additional Insured Coverage

Additional insured endorsements typically cost less than many professionals expect:

Fee Type	Cost Range	Notes
Per-Certificate Fee	$0-$50	One-time administrative fee
Annual Endorsement	$100-$500	For ongoing relationships
Blanket Additional Insured	$250-$1,000	Covers all contracted clients automatically
Premium Increase	0-5%	Depends on number and risk profile

When carriers charge vs. include free:

Some carriers include a limited number of additional insured endorsements at no cost (typically 1-3 per policy year). After that, they charge a per-certificate fee. High-volume professionals should consider a blanket additional insured endorsement, which automatically covers all clients you're contractually required to add.

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Real-World Additional Insured Examples

Example 1: IT Security Consultant

Sarah runs a cybersecurity consulting firm and signs a contract with a regional healthcare system to audit their HIPAA compliance. The contract requires her to add the healthcare system as an additional insured on her professional liability policy.

She contacts Hartford, provides the hospital's information, and receives the endorsement within 24 hours. Three months later, a breach occurs at the hospital unrelated to Sarah's work. Because the additional insured coverage only applies to Sarah's services, her policy doesn't respond to this claim.

Example 2: Management Consultant Subcontracting

David, a strategy consultant, subcontracts to a Big Four consulting firm on a large retail transformation project. The prime contract requires all subcontractors to add the consulting firm as additional insured.

David requests the endorsement from Chubb, paying a $35 certificate fee. When the retail client sues the consulting firm over project delays, David's strategy recommendations are questioned. Because the Big Four firm is an additional insured on David's policy, his professional liability coverage extends to defend them for claims related to David's specific work.

Example 3: Software Developer Enterprise Contract

Jennifer's development shop signs a contract to build custom inventory management software for a manufacturing company. The contract requires additional insured status and a minimum of $2 million in professional liability coverage.

Jennifer's current policy only has $1 million limits, so she increases her coverage and adds the manufacturer as additional insured through Hartford. The total cost: $450 for the increased limits (annual) and $0 for the additional insured endorsement (included in her policy).

Example 4: Event Planner Venue Requirement

Robert provides professional event planning services for a large corporate conference at a convention center. The venue requires all professional service vendors to carry $2 million in liability coverage and add the venue as additional insured.

Robert adds the convention center to his professional liability policy through Chubb for a $50 fee. When an attendee claims the conference content caused them financial harm, the venue is protected under Robert's professional liability coverage for claims related to his event planning services.

Certificate of Insurance vs Additional Insured

Many professionals confuse certificates of insurance (COI) with additional insured endorsements. They serve different purposes:

Certificate of Insurance:
A certificate is simply proof that you have insurance coverage. It shows your policy details, coverage limits, and effective dates. A certificate doesn't extend coverage to the certificate holder - it just proves coverage exists.

Additional Insured Endorsement:
An endorsement actually modifies your policy to extend coverage to the third party for claims related to your work. The additional insured receives actual coverage benefits.

What each provides:

COI: Evidence of insurance, no coverage transfer
Additional Insured: Policy modification, coverage extends to third party

When you need one vs both:

Most contracts require both. The certificate proves you have the required coverage, and the additional insured endorsement actually protects the client. Read your contract carefully - some contracts only require a certificate, while others specifically require additional insured status.

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Carrier Positioning: Hartford vs Chubb

Both Hartford and Chubb offer professional liability additional insured endorsements, but they serve different market segments:

The Hartford:
Hartford is known for competitive pricing and streamlined processes for small to mid-sized professional service providers. Their online portal makes requesting additional insured endorsements straightforward, and they typically process standard requests within 24 hours. Hartford's strength is efficiency and ease of use for consultants and professionals who need frequent certificate requests.

Hartford works well for:

IT consultants with multiple client engagements
Small professional services firms
Consultants needing quick turnaround times
Professionals seeking competitive pricing

Chubb:
Chubb positions itself as a premium carrier for high-risk professional services and complex projects. They offer higher policy limits (often up to $5-10 million) and broader coverage options. Chubb's underwriting is more thorough, which means additional insured requests may take longer but come with more robust coverage.

Chubb works well for:

Large consulting firms
High-risk professional services (large-scale engineering, financial advisory)
Projects requiring very high limits
Professionals seeking premium coverage with fewer exclusions

Both carriers reliably support additional insured endorsements - your choice depends on your coverage needs, budget, and service expectations.

Common Mistakes to Avoid

Waiting until the last minute:
Don't request your additional insured endorsement the day before contract signing. Allow at least one week for processing, especially if you're working with a premium carrier like Chubb that may need additional underwriting review.

Wrong entity name on certificate:
Triple-check the exact legal name of the entity you're adding. "ABC Corporation" is different from "ABC Corp" or "ABC Corporation, Inc." Use the exact legal name from the contract.

Missing required policy period:
Some contracts require additional insured coverage for the entire project duration, including a "tail" period after completion. Make sure your policy period matches the contract requirements.

Not understanding coverage scope:
Additional insured coverage only applies to claims arising from your work. It doesn't give the additional insured full policy benefits. Make sure your client understands this limitation.

Forgetting to update after policy renewal:
Additional insured endorsements typically don't automatically carry over when you renew your policy. You may need to re-request the endorsement with your new policy number.

Not asking about blanket endorsements:
If you regularly add clients as additional insureds, ask your carrier about blanket additional insured coverage. It's usually more cost-effective than individual endorsements.

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Frequently Asked Questions

How much does it cost to add an additional insured to professional liability?

Most carriers charge $0-$50 per certificate for additional insured endorsements. Some policies include 1-3 endorsements per year at no cost. If you need frequent endorsements, consider a blanket additional insured endorsement for $250-$1,000 annually, which automatically covers all contracted clients.

How long does it take to get an additional insured endorsement?

Typical turnaround is 24-48 hours for standard requests. Hartford tends to process requests faster through their online portal (often same-day), while Chubb may take 2-3 business days for more complex projects or high-limit policies. Always request at least one week before you need the certificate.

Is additional insured the same as a certificate of insurance?

No. A certificate of insurance (COI) is simply proof that you have coverage - it doesn't extend coverage to anyone. An additional insured endorsement actually modifies your policy to extend coverage to the third party for claims related to your work. Most contracts require both.

Do both Hartford and Chubb offer additional insured endorsements for professional liability?

Yes, both Hartford and Chubb offer additional insured endorsements on their professional liability policies. Hartford offers a more streamlined online process for standard requests, while Chubb provides broader coverage options for complex or high-risk projects.

Can I add multiple additional insureds to my professional liability policy?

Yes, you can add multiple additional insureds. However, each endorsement may cost $0-$50 depending on your carrier. If you regularly work with multiple clients who require additional insured status, consider a blanket additional insured endorsement that automatically covers all contracted clients.

Does adding an additional insured increase my premium?

Individual additional insured endorsements typically don't increase your base premium - you just pay the per-certificate fee. However, if you add many additional insureds or opt for blanket coverage, carriers may increase your premium by 0-5% to account for the increased exposure.

What information do I need to request an additional insured endorsement?

You'll need: (1) Full legal name of the entity to be added, (2) Their address, (3) Project description or scope of work, (4) Policy period (ongoing or specific project dates), and (5) Certificate holder information. Having this information ready speeds up the process significantly.

Can additional insured coverage be removed mid-policy?

Yes, additional insured endorsements can typically be removed or modified during your policy period. Contact your carrier or agent to request the change. There's usually no fee to remove an additional insured.

Next Steps: Get the Right Professional Liability Coverage

Understanding additional insured requirements is crucial for consultants and professional service providers. Most client contracts require this endorsement, and knowing how to request it efficiently prevents delays in starting new projects.

Before signing contracts that require additional insured status, make sure your professional liability policy can accommodate the requirement. Not all carriers offer the same limits or endorsement options.

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Compare professional liability quotes from Hartford, Chubb, and other top carriers. Our instant quote tool shows you coverage options, pricing, and additional insured endorsement costs in one place. Get the protection you need to confidently sign client contracts and grow your professional services business.