The COI question that trips up more HVAC contractors than any other is this: the GC asks you to be “named as additional insured” on your certificate. You get the certificate. The GC still rejects it. What went wrong? Almost certainly, it comes down to the distinction between a certificate holder and an additional insured — and most HVAC contractors have never had it explained clearly.

Certificate Holder vs. Additional Insured: The Distinction That Costs Contractors Jobs

A certificate holder is listed on the ACORD 25 COI document for notification purposes only. They receive a copy of the certificate and may be notified if your policy cancels. They have no rights under your policy. An additional insured is added directly to your insurance policy via a formal endorsement, giving them the legal right to make a claim against your policy if they are sued as a result of your HVAC work. These are fundamentally different things, and most GCs and property managers want the latter.

Here is where the confusion compounds: your agent can generate a COI listing anyone as a certificate holder instantly. Adding a true additional insured endorsement requires modifying the underlying policy. Both can be done the same day, but they are separate steps. If a GC hands you a contract requirement that says “The GC shall be named as an additional insured,” listing them only as a certificate holder will not satisfy that requirement, and the COI will be rejected.

What Coverages Must Appear on an HVAC Contractor COI

The ACORD 25 form organizes coverage into several categories. For HVAC contractors, the sections that require attention are:

Commercial General Liability

This line shows your per occurrence limit, aggregate limit, products and completed operations limit, and personal and advertising injury limit. Standard commercial contracts require $1 million per occurrence and $2 million aggregate as a minimum. General liability insurance is the most scrutinized section of any HVAC contractor’s COI. The New York Department of Financial Services provides guidance on what COI certificates must and must not include under state law, which applies to any HVAC contractor doing work in New York.

Workers’ Compensation and Employers’ Liability

Workers’ comp appears in its own section of the ACORD 25. Most commercial clients want to see the employers’ liability limits, which are separate from the workers’ comp benefit limits. Standard limits are $100,000 per accident, $500,000 disease policy limit, and $100,000 disease per employee.

Commercial Auto

The auto section should show combined single limit or split bodily injury and property damage limits for any owned, hired, and non-owned vehicles. Commercial clients commonly require $1 million combined single limit for commercial auto liability. A personal auto policy will not satisfy this requirement — and a COI showing personal auto will be rejected.

Umbrella or Excess Liability

Larger commercial projects often require an umbrella policy on the COI. A $1 million umbrella sitting above your general liability is a standard requirement for contracts above $100,000 in project value.

Who Requires a COI from HVAC Contractors and Why

Three categories of clients will routinely demand a COI before work begins:

General Contractors

Any GC who subcontracts HVAC work on a commercial or multi-family project requires the COI for two reasons: to confirm the sub carries sufficient coverage so the GC is not financially exposed for an HVAC-related claim, and to add themselves as an additional insured so they have direct access to the HVAC contractor’s policy if they are pulled into litigation.

Commercial Property Managers

Property managers for office buildings, retail centers, and industrial facilities typically require COIs for any vendor entering their properties. MoneyGeek’s 2026 analysis notes that commercial clients routinely require COIs to be delivered at least 48 hours before work begins. Building their preferred limits and additional insured language directly into your master policy through blanket additional insured endorsements can eliminate most of the per-job COI friction.

Municipal and Government Contracts

Public sector contracts for HVAC work at schools, government buildings, and public facilities carry the most rigorous COI requirements. Expect specific limit requirements listed in the bid documents, mandatory additional insured language, and sometimes a requirement that the government entity receive 30-day advance notice of cancellation.

How to Get a COI and Add Additional Insureds

The process is straightforward when you work with an agent who manages your policy proactively:

1. Contact your agent with the name and address of the party who needs to be listed, their required role (certificate holder only or additional insured), and any specific language the contract requires in the description of operations box
2. If an additional insured endorsement is needed, confirm whether they need ongoing operations coverage, completed operations coverage, or both
3. Request the COI be emailed directly to the party requiring it, and request a copy for your records

The Allen Thomas Group issues certificates the same day for all active HVAC contractor policies. As an independent broker licensed in 27 states, we can also add blanket additional insured endorsements to your policy, which eliminates the per-job request process for frequently recurring clients. Call (440) 826-3676 or visit our HVAC contractor insurance page to get your policy set up or request a COI on an existing policy.

Common COI Mistakes HVAC Contractors Make

The most common COI mistake HVAC contractors make is treating a certificate of insurance as interchangeable with an additional insured endorsement. They are not the same thing. A second common mistake is allowing a COI to expire during an active project without renewing promptly. A 24-hour coverage gap can halt a job and, in some contracts, trigger liquidated damages. Keeping a tickler calendar tied to your policy renewal date prevents both problems.

Additional mistakes worth avoiding:

• Signing contracts that require coverage limits you don’t carry before checking with your agent — confirming a limit you cannot meet creates a coverage gap the moment the contract is executed
• Assuming your personal auto policy covers your work truck — a COI must show a commercial auto policy or it will be rejected
• Using an outdated ACORD 25 form — some commercial clients specify that the COI must be on a current-year ACORD form
• Failing to get COIs from your own subcontractors — if a sub works under your COI and causes a loss, their uncovered work becomes your claim