What Is a COI in Contracting? A Guide

If you’ve never asked a contractor or vendor for insurance paperwork before, it’s normal to feel hesitant or worry it might seem untrusting or slow things down. But this is standard practice, and professional contractors expect this conversation. You’re doing what matters, what’s right, what other professionals like you do, and what protects your interests. A Certificate of Insurance (COI) proves that the people working for you carry coverage. Asking for a COI lays the foundation of every well-managed project.

In this guide, we will walk through:

  • What is a COI in contracting
  • Who is responsible for providing a COI
  • How illumend, powered by myCOI, empowers you to manage COIs with clarity, consistency, and zero guesswork

What Does COI Stand For?

COI stands for certificate of insurance. Think of it as an insurance scorecard: it shows what coverage a contractor has, how much protection they're carrying, and when the protection expires. You leave guesswork behind because you're not making a business decision based on someone's word. You're making it based on verified information and building stronger partnerships.

Why Do You Need a COI from Contractors?

If a vendor without insurance damages property or injures someone while working for you, the cost often falls back on your business. COIs with adequate insurance coverages help you avoid taking on someone else’s risk and keep your projects protected from workplace issues.

A certificate of insurance cannot prevent accidents. But it does protect your business from absorbing costs that aren't your responsibility.

Here’s why you need a COI:

  • Confirms the coverage is active
  • Shows coverage types and limits
  • Builds professional relationships
  • Saves time by providing the right paperwork upfront
  • Prevents conflicts by making responsibilities clear
  • Supports safer work

illumend empowers project managers, operations coordinators, and small business owners like you by flagging missing COIs, confirming coverage types, and automatically managing your COIs.

What Is a COI for a Contractor?

For a contractor, a COI is their way of saying they have the required coverage. It shows they take their business seriously and they're prepared if something goes wrong on your site.

A COI includes:

  • Who the insurance provider is
  • How much coverage they have
  • When it expires
  • What's not covered
  • Who the certificate holder is

One more thing to look for on a COI is whether the insurance policy lists your company as an additional insured. This addition to the policy protects you directly if something goes wrong. To learn more about how to show additional insurance on a COI read our blog.

Bottom line: A COI shows the contractor is prepared, and you get proof of coverage.

What Coverage Types Should You Request?

Most projects need four main types of coverage. Here's what each one does:

General Liability

This covers property damage or bodily injury caused by the contractor’s work. You're protected if they:

  • Accidentally damage walls, flooring, or fixtures
  • Inadvertently injure someone on-site
  • Cause water damage or other property issues

Worker’s Compensation

This covers medical bills and lost wages if the contractor or their employees get injured while working on your project.

Auto Liability

This covers accidents involving vehicles used for the project, critical for vendors who:

  • Deliver materials to your site
  • Operate service trucks
  • Use personal or company vehicles as part of their work

Umbrella or Excess Liability

This provides additional coverage limits on top of general and auto liability, often required for:

  • Higher-value contracts
  • Projects with higher risks
  • Multiple subcontractors working on-site simultaneously

Who Is Responsible for Providing a COI?

The contractor or vendor provides the COI. They reach out to their insurance company and request that you receive the document before the work begins. It's their responsibility because it shows their commitment and professionalism. 

Here’s how it works in practice:

  • A general contractor shares a COI before starting a renovation.
  • An electrician provides proof of workers’ compensation for their team.
  • A landscaping company submits a COI for ongoing maintenance work.

Rule of thumb: Each subcontractor hired for the project provides their own COI rather than combining it with the main contractor's. When you do this, you're being clear and professional. Vendors respect that and help you build a partnership where both the contractor and you understand and respect each other's needs for protection.

When Should You Ask for a COI?

Always ask for a COI before the vendor begins work. Early communication is key. When you ask upfront, vendors have time to request COIs from their insurance brokers, and you have time to verify everything is in order before work starts.

Here’s the best time to ask for a COI:

  • Hiring contractors or vendors for any project
  • Leasing or renting property to a third party
  • Working with suppliers or delivery partners
  • Hosting or sponsoring events
  • Entering into partnership or client agreements
  • Hiring subcontractors for specialized work
  • When your client or partner requests proof of appropriate insurance coverage from you

The simple rule: Ask for a COI whenever work could lead to costs or forced liabilities your company doesn’t want to take on.

How illumend Makes COI Management Easier

Managing COIs often becomes difficult because there are many vendors, documents, and renewal dates to manage. Without a structured process, coverage gaps or expired policies go unnoticed.

illumend empowers you by creating a clear, consistent workflow for insurance management. You invite vendors to upload their certificates, and the compliance platform organizes all the information for you. You know what’s current and what needs attention.

With Lumie™ to guide you, COI management becomes a part of your standard vendor onboarding and insurance compliance process. Everyone sees the same information, insurance documentation stays up-to-date, and your team can focus on reviewing coverage rather than searching for files or following up manually. Schedule a demo today!