What is an "additional insured" on an insurance policy?
An additional insured is a person or business added to someone else's liability policy so they get protection under it too. In Ontario this comes up most with commercial leases, contracts, and subcontractor work, where one party asks to be named on another's Commercial General Liability policy before the job or lease begins.
Who is an additional insured, in plain terms?
Every liability policy has a "named insured" — the person or business that bought it and whose name is on the declarations page. An additional insured is someone else the named insured agrees to extend coverage to, usually because a contract or lease requires it.
Think of a general contractor who hires an electrician. The electrician carries their own Commercial General Liability (CGL) coverage. The contractor doesn't want to be left exposed if the electrician's work causes injury or damage, so the contract says: add us as an additional insured. The electrician's broker arranges that, and now the contractor also has a form of protection under the electrician's policy for claims arising out of that electrician's operations.
The key idea is direction. Being an additional insured means you are borrowing protection under someone else's policy for liability connected to their work or their premises. It does not turn their whole policy into your policy, and it does not cover your own unrelated mistakes.
Why would someone ask to be added as an additional insured?
The request almost always traces back to a written agreement. A few common Ontario situations:
A landlord leasing commercial or mixed-use space will typically require the tenant to carry CGL coverage and name the landlord (and sometimes the property manager) as an additional insured. If a customer slips in the tenant's unit and sues the building owner too, the landlord wants access to the tenant's coverage.
A general contractor or property developer requires subtrades to add them before work starts. If a subtrade's crew damages the structure or injures a bystander, the contractor can be pulled into the claim, and the additional insured status gives them a layer of protection tied to that subtrade's operations.
A client or municipality may require a vendor to name them before signing a service contract, hosting an event, or working on their site.
In each case the party asking is managing their own risk. They are saying, in effect, "if your work or your space causes a problem that lands on me, I want to be protected under the policy that covers that work."
How is someone actually added, and what proof is there?
Two things usually happen together.
First, the broker adds the additional insured to the policy. Depending on the insurer and the situation, this may be done by a general endorsement, a blanket "additional insured as required by written contract" wording, or a specific named endorsement listing that party. The exact wording and scope depend on the policy and the insurer, so it is worth confirming the form matches what the contract asks for.
Second, the broker issues a Certificate of Insurance (COI). This is the one-page document the other party actually collects and keeps on file. It summarizes the coverage, the limits, the policy dates, and shows who has been named as an additional insured. A certificate on its own is a snapshot for information; the endorsement on the policy is what creates the actual coverage. That is why it matters to have both done properly rather than just handing over a certificate.
If you are ever asked to "just send a certificate," it is still a good idea to check whether the contract also requires the additional insured endorsement, because many do. Your broker can read the insurance clause in the agreement and set it up to match.
What does additional insured status actually cover, and what are its limits?
This is where plain language helps, because the protection is narrower than people often assume.
Additional insured status generally extends to liability arising out of the named insured's work, operations, or premises. So the contractor named on the electrician's policy is protected for claims connected to that electrician's work. It is shared protection for a shared exposure.
It does not cover the additional insured's own independent negligence that has nothing to do with the named insured. The landlord named on a tenant's policy is not covered for the landlord's own separate liability elsewhere in the building. The general contractor named on a subtrade's policy is not covered for a different subtrade's mistake.
It also does not replace carrying your own policy. A landlord still needs their own commercial property and liability coverage. A contractor still needs their own CGL. Being named on someone else's policy is a supplement, not a substitute.
And it does not increase anyone's limits for free from your side. The additional insured draws on the named insured's limits. If those limits are low, the protection everyone is relying on is low too, which is why contracts often specify a minimum limit.
How is an additional insured different from a loss payee or a named insured?
These terms get mixed up constantly, so it helps to separate them.
A named insured owns the policy and has the fullest rights under it, including the ability to make changes and the responsibility to pay premium.
An additional insured borrows liability protection under that policy for exposures tied to the named insured's work or premises, as described above. It is a liability concept.
A loss payee or mortgagee is a property concept, not liability. It names a party, often a lender or finance company, who is entitled to be paid for physical damage to insured property. A bank financing a commercial building or a leased vehicle is typically a loss payee, because they have a financial stake in the asset itself.
A quick way to keep them straight: additional insured is about who gets protected if someone gets sued; loss payee is about who gets paid if property is damaged.
What should Ontario business owners and landlords check before signing?
A few practical habits save a lot of friction.
Read the insurance clause in any lease or contract before you agree to it, and send it to your broker. The clause usually states the coverage type, the minimum limits, whether additional insured status is required, and sometimes specific wording. Matching it exactly is what prevents a signed deal from stalling.
Confirm whether you need to add someone, or someone needs to add you. Both directions are common, and they are set up differently.
Ask for the endorsement, not just the certificate, when the contract requires additional insured status. The certificate is the proof you hand over; the endorsement is the coverage behind it.
Keep certificates current. They expire with the policy term, and the party relying on them will usually ask for a renewed one each year.
Setting these up correctly at the start is almost always easier than fixing a mismatch after a claim, when everyone is reading the fine print for the first time.
FAQ
Does adding an additional insured cost extra? It depends on the insurer and the situation. Some policies include additional insured endorsements at no extra charge or through blanket wording; others charge a fee per party added. Your broker can tell you how your specific policy handles it before you commit to a contract.
Can I add an additional insured myself, or does my broker have to do it? Changes to a policy are arranged through your broker or insurer, not added unilaterally. If a contract requires it, send the clause to your broker and they will arrange the endorsement and issue the certificate that reflects it.
If I'm named as an additional insured on a vendor's policy, do I still need my own insurance? Yes. Additional insured status only protects you for liability tied to that vendor's work or premises. It does not cover your own separate operations, property, or independent liability, so your own coverage still matters.
This is general information, not advice on a specific policy — talk to a licensed broker about your situation.