An additional insured is added to your policy by endorsement so your insurer will defend and pay them for claims arising out of your work. It is standard on general liability and usually free. On professional liability it is often unavailable, and a contract that demands it typically needs an amendment. Who this is for: Accounting firms handed a client contract with an additional insured requirement.
The short version
- Additional insured status extends your coverage to someone else. A certificate holder gets nothing but paperwork.
- General liability carriers add it routinely, and blanket wording removes the delay every time.
- Most professional liability carriers do not offer it, so the requirement usually needs to be narrowed to general liability.
- Additional insureds share your limits, which is an argument for buying a higher limit when large clients demand it.
- Ask for the endorsement form, not just a note in the certificate description box.
What additional insured status actually gives someone
An additional insured is a party added to your policy by endorsement so that your insurer will defend and indemnify them for claims arising out of your work. It is not a courtesy line on a certificate. It changes who your policy protects.
| Additional insured | Certificate holder | |
|---|---|---|
| Gets defense and indemnity from your policy | Yes | No |
| Named on an endorsement | Yes | No, named only on the certificate |
| Costs extra | Usually little or nothing | Free |
| Shares your limits | Yes | Not applicable |
| Proves anything by itself | The endorsement does | Evidence only |
The professional liability problem
Here is where accounting firms get stuck. Additional insured status is a general liability concept. It was designed for a world where a property owner could be sued for something a contractor did on their site. Professional liability is different: the coverage responds to your negligent act as a professional, and adding your client as an insured would mean insuring them for your work and potentially for their own decisions.
So most professional liability carriers will not add additional insureds at all. A minority will, usually with narrow wording that covers the client only for vicarious liability arising from your services. If a contract demands it, ask your broker which of these three outcomes applies:
- The carrier issues a limited vicarious liability endorsement, which is the best case.
- The carrier declines and the client accepts a certificate confirming the professional liability limit only, which is the common outcome.
- The client insists, and the contract needs an amendment applying the additional insured requirement to general liability alone.
Blanket versus scheduled, and why it matters to you
On your general liability policy, ask for blanket additional insured wording. Blanket wording automatically covers any party you are required by written contract to name, which means a new client on Monday does not need a policy change on Tuesday. Scheduled endorsements list each party individually, and every new client becomes a phone call, a policy change, and a wait.
For a accounting firm signing several client agreements a year, blanket wording is the difference between a certificate in an hour and a certificate next week.
What to send your broker
- The exact legal name of the party to be added, spelled as it appears in the contract.
- The insurance requirements section of the contract, in full.
- Whether the requirement includes primary and non contributory wording or a waiver of subrogation.
- The date work starts, because the endorsement should be effective on or before it.
- Whether the requirement extends to your umbrella or excess policy.
What this looks like in practice
Illustrative example. Numbers are typical of claims we see and are not a promise of how any specific claim would be handled.
The setup: A accounting firm added a large client as an additional insured on general liability, with blanket wording already on the policy.
The claim: The matter started with a bookkeeping engagement where duplicate vendor payments went unnoticed for 14 months. The client lost $96,000 to a bookkeeper who never reconciled the operating account.
The cost: $24,000 in defense costs and $71,000 in settlement, $95,000 in total, paid inside the policy limit after the retention.
The lesson: The general liability piece was handled in an afternoon at no cost. The professional part of the claim stayed on the firm's own Errors and Omissions (E&O) policy, which is exactly how the two are supposed to work.
Frequently asked questions
Q: A client wants to be added as an additional insured. Can I do that?
On your general liability policy, almost always, and usually at little or no cost. On your professional liability policy, often not, because most carriers do not offer additional insured status on that form.
Q: Does adding an additional insured raise my premium?
Rarely by much. If your general liability policy already carries blanket additional insured wording, adding another party costs nothing and needs no policy change.
Q: What is the difference between an additional insured and a certificate holder?
A certificate holder just receives proof that your policy exists. An additional insured is added by endorsement and can actually be defended and paid under your policy. Clients often ask for one and mean the other.
Q: Can adding a client hurt me?
It can share your limits. If a large claim exhausts the limit defending your client, less is left for you. That is one reason higher limits often accompany contracts that demand additional insured status.
Q: Is blanket additional insured wording worth asking for?
Yes, for any accounting firm that signs more than a couple of client contracts a year. It removes the delay every time a new client asks to be named.
Q: Do I need to give the client a copy of the endorsement?
If the contract asks for it, yes. Increasingly clients want the endorsement form itself rather than a certificate note, and it is reasonable to expect your broker to provide it.
How Morrow helps accounting firms
Morrow is a licensed independent commercial insurance brokerage that specializes in accounting & bookkeeping firms. Getting additional insured wording issued correctly and fast is exactly the kind of question we answer every week, and because we place this coverage every day we know which carriers write it well, which forms are broad, and which contract language actually needs an endorsement behind it.
- We read the contract clause and tell you what your current policy already does and does not do.
- We market your account to carriers that have real appetite for accounting firms rather than whoever answers first.
- We issue certificates the same day a client asks, with the endorsements listed correctly.
- We stay on the file at renewal so limits, retroactive dates, and contract requirements do not quietly drift.
Get in touch and we will see how we can help. Tell us what you do, send over any contract that is driving the requirement, and send us the question and we will tell you where you stand. Start at morrowinsure.com or reach the team through the contact options on that page.
One more thing. This article is general information for accounting firms and is not legal advice, tax advice, or a statement of coverage. Policy wording controls in every case, and forms vary by carrier and by state. Have a licensed advisor review your own policy and your own contract before you rely on any of it.
Last updated: Reviewed by the Morrow commercial lines team. Last updated August 2026.