Construction Compliance Checklist: What to Collect From Every Subcontractor

May 8, 2026 · 7 min read

Before a subcontractor sets foot on your job site, you should have a complete set of compliance documents on file. Not because it's bureaucratic — because when something goes wrong, those documents are the difference between a manageable incident and a serious liability exposure.

Here's a practical checklist of what to collect, why each item matters, and how to stay on top of it across multiple projects and subcontractors.

1. Certificate of Insurance (COI)

The COI is the most important document on this list. It proves the subcontractor carries the insurance coverage your contract requires. At minimum, verify:

• General liability — typically $1M per occurrence / $2M aggregate for most commercial projects
• Workers' compensation — required in virtually every state for any sub with employees
• Auto liability — if they're operating vehicles on or to the site
• Umbrella/excess — required on larger projects, check your contract

When you receive a COI, check three things before accepting it:

• Your company is listed as an additional insured on the general liability policy
• The coverage limits meet your contract requirements
• The policy expiration date is after the project completion date — or you have a renewal process in place

COIs expire. This is the document you'll be chasing renewals on most often, so build an expiry tracking process from the start. A 30-day advance alert gives you enough runway to collect a renewal before there's a lapse.

2. Contractor License

Most states require contractors to be licensed for the work they perform. Licensing requirements vary by trade and state — electrical, plumbing, HVAC, and general contracting all have different rules. As the GC, you're responsible for ensuring every sub on your project is properly licensed for the work they're doing.

Collect:

• State contractor license number and certificate
• Any specialty trade licenses required (electrical, plumbing, etc.)
• License expiration date — these need renewal tracking just like COIs

Most state licensing boards have a public lookup tool where you can verify license status in real time. It takes 30 seconds and is worth doing before a sub starts work.

3. OSHA Certifications

OSHA 10 and OSHA 30 cards are required on most commercial and public construction projects. The standard breakdown:

• OSHA 10 — required for all workers on site
• OSHA 30 — required for foremen, supervisors, and site safety personnel

Some states have enacted laws mandating OSHA cards on all construction sites — New York, Massachusetts, and Nevada among them. Check your state's requirements. Even where not legally required, many project owners include OSHA card requirements in their contracts, which flow down to you and your subs.

4. W-9

You'll need a W-9 from every subcontractor for tax purposes — specifically to issue a 1099 at year end if you pay them $600 or more. This is an IRS requirement, not optional.

Collect it before the first payment. It's much harder to chase down after the project is complete.

5. Signed Subcontract Agreement

Every subcontractor should be working under a signed contract before they start. The subcontract defines scope, schedule, payment terms, insurance requirements, indemnification, and dispute resolution. A handshake agreement or email exchange isn't sufficient protection if something goes sideways.

Keep a fully executed copy — signed by both parties — in your project file.

6. Lien Waivers

Lien waivers are collected differently than the documents above — they're transaction-based rather than one-time. There are four types:

• Conditional waiver on progress payment — collected with each pay application, before payment
• Unconditional waiver on progress payment — collected after payment clears
• Conditional waiver on final payment — collected with the final pay application
• Unconditional waiver on final payment — collected after final payment clears

Many states have statutory lien waiver forms — use those if your state requires them. Collecting lien waivers consistently protects you from a sub placing a mechanic's lien on the property after you've already paid them.

7. Safety Data Sheets (SDS) Where Applicable

If a subcontractor is bringing hazardous materials onto the site — solvents, adhesives, coatings, chemicals — OSHA's Hazard Communication Standard (HazCom) requires Safety Data Sheets to be available on site. The sub should provide these; you should keep them in your site safety file.

The Full Checklist

Document	When to Collect	Expires?
Certificate of Insurance	Before work begins	Yes — track renewal
Contractor License	Before work begins	Yes — track renewal
OSHA 10 / OSHA 30	Before work begins	No (but verify)
W-9	Before first payment	No
Signed Subcontract	Before work begins	No
Lien Waivers	Each pay application	N/A
SDS (if applicable)	Before hazardous materials on site	No

The Real Challenge: Keeping It All Organized

Knowing what to collect is the easy part. The hard part is actually collecting it from every subcontractor on every project, tracking expiry dates, and being able to produce any document on demand when an owner, insurer, or attorney asks for it.

Most GCs manage this through a combination of email, shared folders, and spreadsheets. It works until a project gets complex, a PM changes, or someone asks a question you can't quickly answer.

A centralized compliance system — where every sub submits documents through a single link, expiry dates are tracked automatically, and everything is organized by project — eliminates most of the friction. It also gives you a defensible paper trail if something ever goes to dispute.